The Circle of Knowledge: A Classified, Simplified, Visualized Book of Answers (part 9 of 9)

$1200.00 First principal 36. Interest for 6 months -------- 1236. Principal at beginning of second 6 months 37.08 Interest for second 6 months -------- 1273.08 Principal at beginning of third period 38.19 Interest for third period -------- 1311.27 Principal at beginning of fourth period 39.34 Interest for fourth period -------- $1350.61 Amount at end of two years ======== $1350.61 Amount at end of two years 1200.00 Principal -------- 150.61 Compound interest.

EXCHANGE

in commerce is a method of making payments in distant places, without the actual transmission of money, but by a Bill of Exchange called Draft, which is a written request upon one person to pay a certain sum to another or to his order. The person who orders the money to be paid, is called the Drawer; the one who is directed to pay it, the Drawee, and the one to whom it is directed to be paid, the Payee.

Domestic or Inland Exchange is exchange between places in the same country: Foreign Exchange, between different countries.

If, for every little business transaction, money had to be sent from one business center to another, much needless inconvenience and expense would be incurred.

A man in Chicago owes a man in New York City a sum of money. He can send it to him in one of five ways:--

1. By Check.

2. By Post-office Order

3. By Express Order

4. By Bill of Exchange

5. By Telegraph

Suppose Mr. White of Chicago owes Mr. Brown of Boston $200 for groceries and Mr. Allen of Boston owes Mr. Warner of Chicago $200 for rent. Wouldn’t it save expense and trouble if Mr. White should go to Mr. Warner and Mr. Allen to Mr. Brown? Thereby two debts are cancelled by two city transactions and no money need be sent from one city to another.

This is all there is to Exchange, only in business life banks instead of individuals transact the business.

Only a small percentage of the money really passes from one city to another.

Exchange in the United States is carried on mostly by banks located in the large cities, which charge a small fee for transacting the business.

TABLE OF COMMERCIAL LAW IN THE STATES

=====================================================================+ INTEREST LAWS | ----------------+----------------------------------------------------+ LEGAL RATE | PER CENT ALLOWED BY CONTRACT | PER CENT | AND PENALTY FOR USURY | ----------------+----------------------------------------------------+ Alabama 8| 8; Forfeit interest | Arizona 6| 12; No provision | Arkansas 6| 10; Forfeit principal and interest | California 7|Any; No provision | Colorado 8|Any; No provision | Connecticut 6| 15; Fine or imprisonment, or both | Delaware 6| 6; Principal and interest forfeited | Dist. of Col. 6| 6; Forfeit interest | Florida 8| 10; Forfeit interest | Georgia 7| 8; Forfeit excess of interest | Idaho 7| 12; Forfeit interest and 10% of principal | Illinois 5| 7; Forfeit interest | Indiana 6| 8; Excess interest forfeited | Iowa 6| 8; Forfeit interest and 8% of principal | Kansas 6| 10; Forfeit of double amount of usurious interest | Kentucky 6| 6; Forfeit of interest | Louisiana 5| 8; Forfeit interest | Maine 6|Any; No provision | Maryland 6| 6; Forfeit interest | Massachusetts 6|Any; No provision | Michigan 5| 7; Forfeit interest | Minnesota 6| 10; Forfeit interest | Mississippi 6| 10; Forfeit interest | Missouri 6| 8; Forfeiture or misdemeanor | Montana 8|Any; No provision | Nebraska 7| 10; Forfeit interest | Nevada 7|Any; No provision | New Hampshire 6| 6; Forfeit three times excess | New Jersey 6| 6; Forfeit interest and costs | New Mexico 6| 12; Forfeit of twice the amount of interest | New York 6| 6; Forfeit of principal and interest; misdemeanor | North Carolina 6| 6; Forfeit interest | North Dakota 7| 12; Forfeit interest | Ohio 6| 8; Forfeit interest over 6% | Oklahoma 6| 10; Forfeit interest | Oregon 6| 10; Forfeit principal and interest | Pennsylvania 6| 6; Forfeit excess of interest | Rhode Island 6|Any; No provision | South Carolina 7| 8; Forfeit interest | South Dakota 7| 12; Misdemeanor | Tennessee 6| 6; Forfeit of excess interest | Texas 6| 10; Forfeit interest | Utah 8| 12; Forfeit excess interest | Vermont 6| 6; Forfeit of excess interest | Virginia 6| 6; Forfeit interest | Washington 6| 12; Forfeit of double accrued interest and costs | West Virginia 6| 6; Forfeit excess interest | Wisconsin 6| 10; Forfeit treble amount of usurious interest paid| Wyoming 8| 12; Forfeit interest | ----------------+----------------------------------------------------+

=========================================+===================== STATUTES OF LIMITATION | EXEMPTION LAWS --------------+---------+-------+--------+---------+----------- |JUDGMENTS| NOTES | OPEN |PERSONAL |HOMESTEAD, | | |ACCOUNTS|PROPERTY,| EXEMPT | | | | EXEMPT | --------------+---------+-------+--------+---------+----------- Alabama | 20 yrs. | 6 yrs.| 3 yrs. | $1,000 | $2,000 Arizona | 4 yrs. | 4 yrs.| 3 yrs. | 500 | 2,500 Arkansas | 10 yrs. | 5 yrs.| 3 yrs. | 500 | 2,500 California | 5 yrs. | 4 yrs.| 4 yrs. | ... | 5,000 Colorado | 6 yrs. | 6 yrs.| 6 yrs. | ... | 2,000 Connecticut | 7 yrs. | 6 yrs.| 6 yrs. | ... | 1,000 Delaware | 10 yrs. | 6 yrs.| 3 yrs. | 200 | ... Dist. of Col. | 12 yrs. | 3 yrs.| 3 yrs. | 300 | ... Florida | 20 yrs. | 5 yrs.| 3 yrs. | 1,000 |160 acres Georgia | 7 yrs. | 6 yrs.| 4 yrs. | 300 | 1,600 Idaho | 6 yrs. | 5 yrs.| 4 yrs. | ... | 5,000 Illinois | 20 yrs. |10 yrs.| 5 yrs. | 400 | 1,000 Indiana | 20 yrs. |10 yrs.| 6 yrs. | 600 | or 600 Iowa | 20 yrs. |10 yrs.| 5 yrs. | 200 |or 40 acres Kansas | 5 yrs. | 5 yrs.| 3 yrs. | ... | 160 acres Kentucky | 15 yrs. |15 yrs.| 5 yrs. | 250 | 1,000 Louisiana | 10 yrs. | 5 yrs.| 3 yrs. | ... |Total 2,000 Maine | 20 yrs. |20 yrs.| 6 yrs. | ... | 500 Maryland | 12 yrs. | 3 yrs.| 3 yrs. | 100 | ... Massachusetts | 20 yrs. | 6 yrs.| 6 yrs. | ... | 800 Michigan | 6 and 10| 6 yrs.| 6 yrs. | 500 | 1,500 Minnesota | 10 yrs. | 6 yrs.| 6 yrs. | 500 | 80 acres Mississippi | 7 yrs. | 6 yrs.| 3 yrs. | ... | 2,000 Missouri | 10 yrs. |10 yrs.| 5 yrs. | 300 |1,500(min.) Montana | 10 yrs. | 8 yrs.| 5 yrs. | ... | 2,500 Nebraska | 5 yrs. | 5 yrs.| 4 yrs. | 500 |or 2,000 Nevada | 6 yrs. | 6 yrs.| 4 yrs. | ... | 5,000 New Hampshire | 20 yrs. | 6 yrs.| 6 yrs. | ... | 500 New Jersey | 20 yrs. | 6 yrs.| 6 yrs. | 200 | 1,000 New Mexico | 7 yrs. | 6 yrs.| 4 yrs. | 500 | 1,000 New York | 20 yrs. | 6 yrs.| 6 yrs. | 250 | 1,000 North Carolina| 10 yrs. | 3 yrs.| 3 yrs. | 500 | 1,000 North Dakota | 10 yrs. | 6 yrs.| 6 yrs. | 1,000 | 5,000 Ohio | 5 yrs. |15 yrs.| 6 yrs. | 100 | 1,000 Oklahoma | 5 yrs. | 5 yrs.| 3 yrs. | ... | 5,000 Oregon | 10 yrs. | 6 yrs.| 6 yrs. | ... | 1,500 Pennsylvania | 20 yrs. | 6 yrs.| 6 yrs. | 300 | ... Rhode Island | 20 yrs. | 6 yrs.| 6 yrs. | 800 | ... South Carolina| 20 yrs. | 6 yrs.| 6 yrs. | 500 | 1,000 South Dakota | 20 yrs. | 6 yrs.| 6 yrs. | 750 | 5,000 Tennessee | 10 yrs. | 6 yrs.| 6 yrs. | ... | 1,000 Texas | 10 yrs. | 4 yrs.| 2 yrs. | 500 | 5,000 Utah | 8 yrs. | 6 yrs.| 4 yrs. | ... | 2,000 Vermont | 8 yrs. | 6 yrs.| 6 yrs. | 200 | 500 Virginia | 20 yrs. | 5 yrs.| 2 yrs. | ... | 2,000 Washington | 6 yrs. | 6 yrs.| 3 yrs. | 1,000 | 2,000 West Virginia | 10 yrs. |10 yrs.| 5 yrs. | 200 | 1,000 Wisconsin | 20 yrs. | 6 yrs.| 6 yrs. | 200 | 5,000 Wyoming | 5 yrs. | 5 yrs.| 8 yrs. | 500 | 1,500 --------------+---------+-------+--------+---------+-----------

NOTE.--In many of the States it is impossible to place a fixed amount on personal property exempt. In the table above these states have no amount given in the personal property column. Days of grace have been abolished in all states except the following: Arkansas, Mississippi, South Carolina and Texas.

If the drawee accepts the draft, he writes across the face of it “Accepted” with the date and his signature. This is called an Acceptance.

Once accepted, the draft becomes a note, with the same laws regulating it. If the draft is not accepted, it is not binding and we say that it has been “dishonored.”

A bill of exchange is entitled to days of grace, if it is payable in a State where grace is allowed, unless a particular day is named in the draft. In most States, no grace is allowed on sight drafts.

PRINCIPLES OF EXCHANGE

To find the cost of a draft, the face and rate per cent of exchange being given.

RULE.--Find the percentage of the given rate per cent of exchange and add it to, or subtract it from the amount of draft.

EXAMPLE: What is the cost, in Chicago, of a sight draft on Denver for $400, if exchange is 3/4% premium; and how much if 1/2% discount?

$400 × .00-3/4 = $3; $400 + $3 = $403, at 3/4% premium.

$400 × .00-1/2 = $2; $400 - $2 = $398, at 1/2% discount.

To find the face of a draft, cost and rate per cent of exchange given.

RULE.--Divide by the cost of a draft for $1, at given rate per cent of exchange.

EXAMPLE: Find face of draft that can be bought for $1000 at 1% premium; at 1% discount.

$1000 ÷ 1.01 = $990.10, at 1% premium.

$1000 ÷ .99 = $1010.10, at 1% discount.

Time Drafts, when negotiated before maturity, are subject to discount which is computed on the face of the draft, the same as interest.

EXAMPLE: What is the proceeds of a 60-day draft for $800, at 5/8% premium, and discounted at 7%?

$805.00, face + 5/8% premium 9.33, interest (7%, 60 days) ------- $795.67, proceeds. Ans.

Foreign Drafts are usually made payable in the money of the country on which they are drawn.

To find the equivalent of foreign money in United States money and vice versa.

RULE.--Multiply, or divide (as the case may require) the given sum, by the equivalent of a unit in United States money.

EXAMPLE: What is the cost of a draft on London for £125, reckoning exchange at $4.8665?

125 × 4.8665 = 608.31. Ans. $608.31.

Wishing to remit $182.50 to Ireland, for what amount must I buy a draft on London?

182.50 ÷ 4.8665 = 37.5. Ans. £37-1/2.

How many francs in $100?

100.000 ÷ .193 = 518.13. Ans. 518.13 francs.

How many dollars in 7500 German marks?

7500 × .238 = $1785, Ans.

How many Swedish crowns in $750?

750 ÷ .268 = 2798-1/2 crowns, Ans.

How many dollars in 4635 rubles?

4635 × .772 = $3578.32, Ans.

A simple method to reduce pounds sterling to United States money, and vice versa; exchange being at $4.8665.

RULE.--Multiply pounds sterling by 73, and divide the product by 15. Or multiply dollars by 15 and divide the product by 73.

EXAMPLES: How many dollars in £85?

85 × 73/15 = 413.67. Ans. $413.67.

How many £’s in $748.25?

748.25 × 15/73 = 153-3/4. Ans. £153-3/4.

Another method to change pounds sterling, shillings and pence, to dollars and cents.

RULE.--Reduce pounds sterling to shillings, add the shillings, and multiply the sum by .24-1/3--the product will be cents. Add 2 cents for each pence, if any.

EXAMPLE: Change £46, 13s. 9d. to United States money.

46 × 20 = 920 933 × .24-1/3 = 227.03 13 9d. = .18 --- ------- 933 Ans. $227.21

Tourists of today patronize express companies for Foreign Money Orders. These are made out similar to regular express money orders and may be cashed in any of the larger cities of all foreign countries. They take the place, to a large extent, of Letters of Credit, which are letters from banking houses in one country to those in another, allowing sums to be drawn not to exceed a total named in the letter.

STOCKS AND BONDS

Stocks is a general name given to the capital of incorporated companies. They are divided into equal parts, usually of $100 each, called Shares, the owners of which are called Stockholders. A Dividend is a part of the net income of the company, divided among the stockholders.

A certificate of stock is a written paper signed by the proper officers of the corporation, naming the number of shares to which the person named therein is entitled, and the original value of the same.

Preferred stock is stock which is given a preference over the common stock. Ordinarily, a dividend is paid on the preferred stock before any is paid on the common shares.

Common stock is the ordinary stock of a corporation, which has no preference, in the payment of dividends, over any other.

The par value of a share of stock is the value named in the certificate of stock.

When a corporation is prosperous, its shares of stock often sell for more than the value named in the certificate of stock. They are then said to be above par, or at a premium. In times of business depression, often these shares of stock sell below their face value. They are then said to be below par, or at a discount.

The market value of a share of stock is the value for which it sells in the open market.

A stock broker is one who makes a business of buying and selling stocks and bonds. He charges a commission for this which is called brokerage.

A surplus is a part of the earnings of a corporation.

The gross earnings of a corporation are its total receipts from all sources.

The net earnings are the profits remaining when all expenses, losses, interest and debts due are paid.

An assessment is a sum levied proportionate to stock held by stockholders, to help out the business when it is not prospering, or when more money is needed to carry it on. It is levied as so many dollars on each share at its par value.

The directors are those shareholders elected by all to manage the affairs of the corporation.

A bond is, in form, a carefully drawn interest-bearing promissory note. Ordinarily, it runs for a period of years with interest often payable semi-annually. It is more formal than the ordinary promissory note. Bonds are usually issued by national, state, county, or local governments, or by corporations, when they wish to raise large sums of money for immediate use.

DIFFERENCE BETWEEN STOCKS AND BONDS

A bond runs for a specified time. It bears a specified interest, and is an absolute promise to pay the face of it at maturity. It matures at a definite time, and at that time the holder is paid its face value and no more, by the organization that issued it, unless such organization is insolvent, or has repudiated its debts.

Stocks.--A certificate of stock is no promise to pay. It simply shows that the holder owns as much stock in the corporation as is shown by the face of the certificate. It bears no interest and has no date of maturity.

The interest returns of the bondholder are certain and definite. The returns of the stockholder, dividends, are uncertain and depend on the profits of the business.

Consequently, no table can be arranged to show at what rate stocks can be bought to yield a definite return; but with bonds, tables may be made which show at a glance what the return will be from a purchase made at any rate.

APPLICATION OF PERCENTAGE TO STOCKS

1. To find the value of stocks, when above or below par.

RULE.--Multiply the price per share, by the number of shares.

EXAMPLE: Find cost of 65 shares of bank stock, at $107 per share, or 7% premium. Also of 48 shares of railroad stock, at $87-1/2 per share, or 12-1/2% discount.

(1) 65 × 107 = 6955. Ans. $6955.

(2) 48 × 87-1/2 = 4200. Ans. $4200.

2. To find what rate per cent is realized by investing in stocks or bonds when above or below par.

RULE.--Annex two ciphers to the fixed rate per cent, and divide by the cost per share. Or by proportion: As the cost per share is to the fixed rate, so is 100 to the required rate.

EXAMPLE: Mr. Warren bought ten shares of Illinois Central Railroad stock at 96. What does he get when a dividend of 6% is declared? What per cent is that on his investment?

WORK AND EXPLANATION:

(1) 1 share at 6% yields $6 10 shares yield 10 × $6 = $60.

(2) Each share at 96 costs $96. Each share yields $6.

Query? $6 is what per cent of $96? $6 is 6/96 of 100%, or 6-1/4%. ∴ the investment yields 6-1/4%.

3. To find which is the more profitable investment.

RULE.--Find the rate per cent that each investment yields, by rule, under item 2; then compare rates.

EXAMPLE: Which is the better investment; 6% mortgages at 10% premium, or 5% bonds at 10% discount?

(1) 110)600(5-5/11%.

(2) 90)500(5-5/9%. 5/9 - 5/11 = 10/99, practically 1/10.

Ans. The latter, by 1/10 of 1%, nearly.

TAXES AND TAXATION

A tax is a contribution levied on persons, property, incomes, or business, for public purposes.

SOME USES FOR TAXES.--The National Government requires money to support the army and navy, to pay the salaries of government employes, to pay pensions, and to finance other activities carried on by the nation.

The State Governments require money for the expense of their officers, and to support their various institutions, schools, universities, asylums, and penitentiaries.

The counties require money for the building of bridges, the trial of criminal cases, the salaries of officers, the relief of the poor, etc.

Cities must pay for police and fire protection, care of streets, etc.

School districts contribute to the support of the public schools.

The money required for all these expenses is raised by taxes, licenses, fees, assessments, and fines.

STATE AND LOCAL TAXES.--The amount of tax paid by any individual to state and local governments depends upon the value of the property which he owns and the tax rate. In many places the adult male citizen pays a poll tax.

The tax levied on property is called a property tax.

The tax levied on persons is called a poll tax. This is sometimes called a capitation (by the head) tax.

Sometimes a man’s income is taxed. This is an income tax.

After the amount of money to be raised by tax is decided upon, a man, called the assessor, examines each piece of taxable personal property and real estate, and places a value upon it. This is taken as a basis for proportioning the tax among the property owners.

A tax collector is one who collects the taxes. He is sometimes paid a salary. Sometimes he gets only a percentage of the money he collects.

The treasurer receives and takes care of the money collected by the tax collector. He is paid a salary.

THE TAX RATE.--Sometimes the rate is fixed by law or by vote of the citizens. More often the lump sum to be raised is named, and the assessor determines the rate.

When the assessor is to determine the rate, he proceeds in this way: First, he assesses each piece of property, usually not at its full market value. Then he determines the total value of all the property in his district. Next, he divides the total tax to be raised by the total value of the property in his district. The result is the rate of tax on the dollar.

USE OF THE MILL IN TAXES.--When a tax is apportioned, it is usually found that if a few mills are paid on each dollar’s worth of property in the district, the aggregate amount is equal to the whole sum of tax needed. Consequently, we often hear of tax levies of so many mills on the dollar, as, 2 mills on the dollar, 5 mills on the dollar, etc.

The denomination of our money system called the mill has practically its only use in the levy of taxes.

Assessors make use of a table like the one given on the following page. This table is based on a tax levy of 9 mills on the dollar.

The following tax rates are equivalent:

16 mills (on the dollar);

1.6%;

$1.60 (on each hundred dollars).

EXPLANATION OF TABLE. The second column shows the tax at nine mills on the dollar, for values of $1 to $30. The fourth column shows the tax for values of $40 and multiples of ten, to $600. The sixth column shows the tax for values of $700 and multiples of one hundred, to $10,000.

TAX TABLE

========+========+========+=======+=========+======= PROPERTY| |PROPERTY| |PROPERTY | VALUE | TAX | VALUE | TAX | VALUE | TAX --------+--------+--------+-------+---------+------- $ 1 | $0.009 |$ 40 | $0.36 |$ 700 |$ 6.30 2 | 0.018 | 50 | 0.45 | 800 | 7.20 3 | 0.027 | 60 | 0.54 | 900 | 8.10 4 | 0.036 | 70 | 0.63 | 1,000 | 9.00 5 | 0.045 | 80 | 0.72 | 2,000 | 18.00 6 | 0.054 | 90 | 0.81 | 3,000 | 27.00 7 | 0.063 | 100 | 0.90 | 4,000 | 36.00 8 | 0.072 | 200 | 1.80 | 5,000 | 45.00 9 | 0.081 | 300 | 2.70 | 6,000 | 54.00 10 | 0.09 | 400 | 3.60 | 7,000 | 63.00 20 | 0.18 | 500 | 4.50 | 8,000 | 72.00 30 | 0.27 | 600 | 5.40 | 9,000 | 81.00 --------+--------+--------+-------+---------+-------

THE AMOUNT OF TAX.--To find the amount of tax to be paid by any property owner.

Rule.--Multiply the assessed value of the property by the tax rate.

EXAMPLE: Taylor’s property is assessed at $3800. The rate is 24 mills.

SOLUTION: $3800 assessed valuation .024 tax rate in mills ------ $91.20 tax.

EXAMPLE: The town of Grant is to raise $4725 in tax. The property in the town has an assessed valuation of $395,140. What is the rate?

If on $395,140 a tax of $4725 is to be raised, on $1 as much tax must be raised as $395,140 is contained times in $4725, which is .0119+, or about $.0119. This would be called $0.012, or 12 mills on the dollar.

EXAMPLE: Finch’s property is assessed at $5470. The tax rate is $1.95.

SOLUTION: $1.95 the rate per hundred dollars 54.70 the number of hundreds of dollars assessed value ------- $106.67 the tax.

INDIRECT TAXES are taxes placed upon goods by the national government, and collected before the goods are sold to the consumer.

The national government needs this money to pay:--

1. Interest on the public debt.

2. To support an army and navy, to build vessels, and keep up arsenals and forts.

3. To pay pensions.

4. To improve the rivers and harbors.

5. To pay the salaries of its officers; as, the president, cabinet officers, judges, ministers to foreign countries, congressmen, etc.

Indirect taxes are of two kinds, customs or duties, and excises or internal revenue.

Excises or internal revenue are taxes levied on certain domestic goods, as, manufactured tobacco, liquors, and the like.

Indirect taxes levied by the government on imported goods or merchandise are called duties or customs.

A custom house is a government office where duties are collected and where vessels are entered and cleared. Nearly every seaport of consequence has a custom house. So also have important towns near the Canadian and Mexican boundaries.

Duties are of two kinds, specific and ad valorem.

A specific duty is one levied at a specified sum per yard, gallon, ton, etc.

An ad valorem duty is one levied at a certain percentage of the value of the goods, at the port of export.

Tare is an allowance made for the weight of bags, barrels, or cases, in which merchandise is shipped.

Leakage is an allowance made for loss of liquids from casks, barrels, etc., in shipping.

Breakage is an allowance made for the loss of liquids from bottles in shipping.

EXAMPLE: Find the duty on 4 dozen bottles of cologne, allowing 4% for leakage and 3% for tare. The invoice value is 90 cents a bottle and the duty is 25% ad valorem and 20 cents specific. Find the total cost per bottle.

WORK AND EXPLANATION:

Leakage and tare are 4% + 3% = 7%.

4 dozen bottles = 48 bottles.

The invoice value of 48 bottles is 48 × 90 cents = $43.20 Tare and leakage are 7% of $43.20 = $ 3.024 -------- Value on which duty is paid $40.176

Ad valorem duty is 25% of $40.176 = $10.044 Specific duty is 48 × 20 cents = 9.60 -------- Total duty $19.644

The total cost is

Invoice value $43.20 Ad valorem duty 10.04 Specific duty 9.60 ------ $62.84

The total cost per bottle is 1/48 of $62.84, or $1.31-.

SQUARE ROOT AND CUBE ROOT

POWERS AND ROOTS.--When a product consists of the same factor repeated any number of times it is called a power of that factor.

7 × 7 is the second power, or the square of 7.

7 × 7 × 7 is the third power, or the cube of 7.

A power of a number is generally expressed by writing the number only once, and placing after it, above the line, a small figure to show how many factors are to be taken. The small figure is called an index.

Thus, 7² = 49; 7³ = 343; 7⁴ = 2401.

A number is called the square root of its square.

Since 7² = 49, the square root of 49 is 7.

The “square root of 49” is written √49.

Again, a number is called the cube root of its cube. 7³ = 343. Therefore, the cube root of 343 is 7.

The “cube root of 343” is written ∛343.

A perfect square is a number whose square root is a whole number. A perfect cube is a number whose cube root is a whole number.

SQUARE ROOT.--If a number can be put into prime factors, its square root can be written down by inspection.

EXAMPLE: Find the square root of 27225.

Since 27225 = 3² × 5² × 11².

∴ √27225 = 3 × 5 × 11 = 165 Ans.

RULE FOR DIGITS.--We know that √1 = 1, and √100 = 10. Therefore, the square root of any number which lies between 1 and 100 lies between 1 and 10; i.e., if a number contains one or two digits, its square root consists of one digit.

Similarly, since √100 = 10 and √10000 = 100, the square root of a number between 100 and 10000 lies between 10 and 100. That is, if a number contains three or four digits, its square root consists of two digits.

Proceeding in this way, we obtain a general result--viz., the square of a number has either twice as many digits as the number, or one less than twice as many.

Hence, to ascertain the number of digits in the square root of a perfect square, mark off the digits in pairs, beginning from the right. Each pair marked off gives a digit in the square root; and, if there is an odd digit remaining, that digit also gives a digit in the square root.

EXAMPLES: There are three digits in the square root of 546121, and four in the square root of 5774409.

For, marking off the digits from the right, we get in the first case 54,61,21, giving three digits in the square root, and in the second case 5,77,44,09, the odd digit giving the fourth in the square root.

The method of finding the square root of a given number depends on the form of the square of the sum of two numbers.

EXPLANATION: The square root of 144 is 12. Let us see how we found it.

12 = 1 ten + 2 units.

12² is the same as (10 + 2)².

Let us square (10 + 2), that is, multiply 10 + 2 by 10 + 2.

10 + 2 10 + 2 --------------- 10² + (10 × 2) + (10 × 2) + 2² -------------------- 10² + 2(10 × 2) + 2²

Then, 12² = 10² + 2(10 × 2) + 2²

RULE.--The square of any number made up of tens and units is equal to the square of the tens, plus twice the product of the tens by the units, plus the square of the units.

ANOTHER EXPLANATION: Find the square root of 45369.

SOLUTION:

4·53·69)213 4 --- ---+-------- 41|53 |41 +---- 423|1269 |1269 +---- |

(1) Point off the number into periods of two figures each, as before.

(2) The square root of the first period is 2. 2 × 2 = 4. Write the 2 in the root and subtract the 4 from 4. Bring down the next period, 53.

(3) 2 × 2 = 4. (Remember the 4 is to be used as a trial divisor, being 2 × the tens.)

4 is contained in 5 about 1 time.

Place 1 in the root, also on the right of the 4 in the divisor. Multiply 41 by 1. Subtract and bring down the next period.

(4) 2 × 21 = 42. 42 is the trial divisor. 126 ÷ 42 = about 3 times. Place the 3 in the root also at the right of the 42 in the divisor. Multiply out.

Square root = 213.

CUBE ROOT.--The cube root of a number is one of the three equal factors of that number.

Thus, 5 is the cube root of 125, because 5 × 5 × 5 = 125.

The radical sign with a figure 3 over it (∛) means that the cube root of the number following it is to be taken.

∛125 reads, “The cube root of 125.”

If we can find the prime factors of any perfect cube, we can write down its cube root by inspection.

EXAMPLE: Find the cube root of 74088.

8|74088 +----- 9| 9261 +----- ∴ 74088 = 8 × 9 × 3 × 7 × 7 × 7 3| 1029 = 2³ × 3³ × 7³ +----- 7| 343 ∴ ∛74088 = 2 × 3 × 7 +----- = 42 Ans. 7| 49 +----- | 7 +-----

RULE FOR DIGITS.--Since 1³ = 1 and 10³ = 1000, therefore the cube of a number which lies between 1 and 10 lies between 1 and 1000, i. e., the cube of a number of one digit contains either one, two or three digits.

Again, since 10³ = 1000 and 100³ = 1000000, the cube of a number of two digits contains either four, five, or six digits.

Proceeding in this way, we see that the cube of a number contains three times, or one less or two less than three times, as many digits as the number.

Hence, to find the number of digits in the cube root of a given number, we mark off the digits in sets of three, beginning at the decimal point, and marking both to the right and to the left.

Thus, 289383 will be pointed off into two periods--289·383--and we readily see there will be only 2 figures in the root.

The simplest method of finding the cube root of numbers whose prime factors are not known is analogous to the method of finding square root, being based upon the form of the cube of the sum of two numbers.

EXPLANATION: The cube root of 1728 is 12. Let us see how we found it.

12 = 1 ten + 2 units 12³ = (10 + 2)³ (10 + 2)³ means 10 + 2 × 10 + 2 × 10 + 2 10 + 2 10 + 2 -------------- 10² + (10 × 2) + (10 × 2) +2² -------------------- 10² + 2(10 × 2) + 2² 10 + 2 ----------------------------- 10³ + 2(10² × 2) + (10 × 2²) + (10² × 2) + 2(10 × 2²) + 2³ ---------------------------------- 10³ + 3(10² × 2) + 3(10 × 2²) + 2³

That is, the cube of any number made up of tens and units equals--

The cube of the tens + three times the product of the square of the tens by the units + three times the product of the tens by the square of the units + the cube of the units,

tens³ + 3(tens² × units) + 3(tens × units²) + units³.

For graphic illustration the geometrical representation of the cube of units and tens in the drawings is helpful.

After the process is understood, this short method of writing the work may be used by the pupil:

EXAMPLE: Find the cube root of .0163956, carrying the root to 3 decimal places.

WORK:

.016·395·600).254+ 8 ------ ------+----- 1200|8395 300| 25| ----+ 1525|7625 +------- | 770600 187500| 3000| 16| ------+ 190516| 762064 +------- | 8536

CHEMISTRY

ITS USE AND IMPORTANCE -- WHAT IT IS -- HOW IT DIFFERS FROM PHYSICS -- ITS DIVISIONS -- DISTINCTION BETWEEN THEORETICAL AND PRACTICAL CHEMISTRY -- OUTLINE OF THEORETICAL CHEMISTRY -- LAWS OF CHEMISTRY -- ATOMIC THEORY -- CHEMICAL NOTATION -- MOLECULAR WEIGHTS -- REACTIONS -- CHEMICAL ARITHMETIC -- BASES -- QUANTIVALENCE -- TESTS -- TABLE OF CHEMICAL ELEMENTS -- -CHEMISTRY OF FAMILIAR THINGS -- COMMON NAMES OF CHEMICALS -- RADIO-ACTIVITY AND RADIO-ACTIVE SUBSTANCES -- RADIUM AND ITS USES -- THE SPINTHARISCOPE

IMPORTANCE OF CHEMISTRY

A certain amount of knowledge of chemistry is eminently useful in almost every walk of life. An intelligent knowledge of the chemistry involved in the processes of the kitchen, the dairy, the dye-house, the farm, or the manufactory, places the possessor engaged in any of these processes on a different level from the rule-of-thumb worker, who is as ignorant of the reason for adopting a particular method as he is of the properties of the materials he employs.

Technical chemistry deals especially with the application of the principles and processes of chemistry to the arts and manufactures, and it is to those who are engaged in manufactures of almost every kind that a knowledge of chemistry is a particular advantage.

It is not a question of expediency alone, but one of absolute necessity that a technical education, including chemistry as one of its principal subjects, should form not the least important part of the equipment for his work of any artisan who is to excel in his employment in intelligence and skill.

What is chemistry?

Chemistry is that branch of science which treats of the intimate composition of matter, and the changes produced in it when subjected to particular conditions--such as temperature, pressure, mass, light, catalysis, etc.

How does chemistry differ from physics?

The two branches, physics and chemistry, overlap a great deal, it being very difficult to draw the line of demarcation between them, particularly in the higher stages of the physical and chemical changes of matter.

For example, a steel needle rubbed on a magnet in a definite way undergoes physical change by means of which it acquires the power of the magnet. On the other hand, a match rubbed on a match-box undergoes a chemical change by means of which flame is produced. Thus it is possible to make a distinction between the sciences of physics and chemistry. A chemical change involves some alteration in the essential nature of the substance. The match having been ignited has undergone a permanent change, whereby it is no longer combustible. The physical change quoted above involves no alteration in the substance itself, and the acquired property is further only temporary and can be continually lost and reacquired.

The difficulty occurs in this fact, however, that every chemical change is accompanied by physical change, and the physical change may often be the only sign that chemical change has taken place.

What are the chief divisions of chemistry?

ORGANIC AND INORGANIC CHEMISTRY.--There are two great divisions in the science of chemistry, organic and inorganic. The branch which is best known is that of inorganic chemistry, which covers the chemistry of all the purely mineral substances. Organic chemistry has to do primarily with that of substances obtained from animal or vegetable sources. Now, however, it has resolved itself into the study of the compounds of carbon, always bearing in mind the fact that many carbon compounds have no organic origin, and therefore really fall outside the scope of organic chemistry.

The fundamentals of both branches are the same, and the real reason for the division is the number of the carbon compounds and their highly complex character. It is in this realm that the graphic formula is of most service, and in its organic branch chemistry most nearly approaches biology.

The branch of inorganic chemistry which treats of the composition, etc., of naturally occurring minerals, receives the title of mineralogical chemistry.

PHYSICAL CHEMISTRY explains processes, formulates laws for these processes, and is divided within itself again into electro-chemistry and thermo-chemistry, etc. One branch of physical chemistry in which great strides have been made, is the study of the general properties of gases. But it is really as much in the realm of physics as it is in the realm of chemistry.

The study of the chemical nature of substances entering into the constitution of the animal organism, and the chemical changes taking place during the life processes of animals, forms the domain of physiological chemistry.

The investigation of the influence of soils, and manures, etc., of different compositions, upon vegetable life, and the chemical principles underlying the art of agriculture, are included in the province of agricultural chemistry.

Pharmaceutical chemistry deals with the nature and mode of preparation of the various drugs, ointments, etc., employed for medicinal purposes.

The science in its relations to the arts, manufactures, and industrial processes is embraced in the wide titles of technical and applied chemistry.

What is the difference between theoretical and practical chemistry?

There are in every science two great divisions. These are known as the “theory” and the “practice” (or, as they are sometimes called, the science and the art). The theory of any science is that part of it which forms the answer in any case to the question “Why?” The practice in the same way answers to the question “How?”

If we find, for example, that by putting a fire under a vessel of water, the water gradually begins to boil, as we say, “boils away,” we have learned something that relates to practice. We have learned how to change water into vapor. It is not necessary that we should know why the result is brought about, so long as we are satisfied with the result alone.

But as soon as we begin to wish to bring about any result in the best possible way, we must inquire why a certain course of action causes the result; and in the case of the water, we ask why heat should make water boil and then disappear. The answer to the question “How?” is usually a simple one. It can be found out by experiment. Once having found out, we may usually repeat the work as often as we choose.

But the question “Why?” lies deeper, and sometimes cannot be answered at all. The answer to it is in all cases merely a guess--an attempt to explain more or less fully and satisfactorily. If we find that our explanation or theory makes it possible to foretell what will happen in new cases, then we may safely trust it and believe in it.

Give a clear, succinct outline of the essentials of theoretical chemistry.

The whole matter of molecules and atoms is one of theory. None of our senses can enable us to know directly either molecules or atoms. We can only imagine that they exist, and then give reasons why their existence makes clear to us the action of elements or of compounds one upon the other.

But in a course of descriptive chemistry, a good knowledge of theoretical chemistry is necessary in order to fully understand all that will be taken up.

THEORETICAL CHEMISTRY

(1) DEFINITIONS.--An element is a substance that cannot be decomposed.

A compound is a substance that can be decomposed into other different substances; and if the decomposition goes far enough, these substances will be elements.

A mixture is made up of two or more components (elements and compounds or both), physically put together. It differs from a compound whose compounds are chemically united.

(2) LAWS.--Law of Definite Proportions: All specimens of a compound contain the same elements in the same proportions.

Law of Multiple Proportions: When two compounds consist of the same elements, the proportion of one is a simple multiple of the proportion of the other.

Law of Combining Proportions: Each element enters into all its compounds by a fixed proportional weight.

The fundamental laws of chemistry are proved by experiment.

(3) THE ATOMIC THEORY.--The atomic theory teaches that matter is composed of minute particles which themselves cannot be divided, but which unite to form molecules which can be divided.

A molecule, then, is the smallest amount of a substance that can exist in a free state.

The diameters of molecules have been ascertained by Jeans to be--

Hydrogen 20.3 Nitrogen 29.1 Oxygen 27.3

These figures express number of billionths of a meter.

An atom is an indivisible particle of an element, and goes to make up the molecule.

(4) CHEMICAL NOTATION.--The symbols used to represent the different elements (e.g. H for hydrogen, O for oxygen, etc.), when used in chemical compounds, refer to the number of atoms which go to make up the molecule of that particular compound. For example, the expression H₂SO₄ means that in one molecule of that acid there are 2 atoms of hydrogen, 1 of sulphur, and 4 of oxygen.

(5) MOLECULAR WEIGHTS.--To determine the molecular weight of a compound it is necessary to know Avogadro’s Law: Equal volumes of all gases under the same conditions contain the same number of molecules; and Molecular Weight = Vapor Density × 2.

(6) REACTIONS.--A reaction or chemical equation is a method of representing a chemical change.

In chemistry we have three kinds of reactions, namely:

(1) Analytical reaction, which is the breaking up of compound bodies into simple, e.g., H₂CO₃ can be broken up into its components, H₂O and CO₂, e.g., H₂CO₃ = H₂O + CO₂.

(2) Synthetical reaction is the building up of a compound body by the union of two or more simple bodies, e.g., H₂ + O = H₂O and H + Cl = HCl.

(3) Metathetical reaction consists in the interchange of two radicals in two substances, e.g.,

2HCl + Zn = ZnCl₂ + H₂. Here the H of the acid is replaced by the Zn.

KCl + AgNO₃ = AgCl + KNO₃. Here the Ag and the K change places.

(7) THE CHEMICAL ARITHMETIC by which from the molecular weights of two substances, and the weight of one substance we are enabled to get the weight of the required substance is called Stoichiometry.

EXAMPLE: Required the amount of zinc necessary to generate 10 grams of hydrogen.

Atomic weights of H, Cl, and Zn are respectively 1, 35.5, and 65.3.

The reaction is as follows:--

Zn + 2HCl = ZnCl₂ + H₂, and shows that 2 atoms of H are used for every 1 of Zn.

(Mol. Wt. Zn.) (Mol. Wt. H₂) (Wt. Zn.) (Wt. H₂.) 65.3 : 2 = x : 10

65.3 × 10 --------- = x = 326.5 grams of Zn. 2

(8) BERTHOLLET’S LAW.--Berthollet established the following law, which is of great importance. When two substances can form a substance insoluble or volatile, under the condition of the reaction, that substance will be formed till one of the factors is exhausted.

(9) RADICALS.--A radical is an atom or group of atoms which changes places in a reaction. A compound radical is made up of different sorts of radicals, as NH₄.

A basic radical is a metal, or a compound radical which behaves like a metal, e.g., Zn and NH₄.

(10) HYDRATES.--A hydrate is a substance formed from water by replacing half of its hydrogen by a radical, e.g., H₂O + 2Na = 2NaOH + H₂, where the sodium has taken the place of one atom of hydrogen.

(11) BASE.--If a hydrate is formed by a basic radical, the hydrate is called a base, e.g., ZnO₂H₂.

(12) ALKALI.--An alkali is a soluble base, e.g., NaOH, KOH, NH₄OH, LiOH.

(13) ACID.--An acid is a substance containing hydrogen which may be replaced by a basic radical, e.g., 2HCl + Zn = ZnCl₂ + H₂.

(14) SALTS.--A salt is a substance formed from an acid replacing its hydrogen by a basic radical, e.g. 2HCl + Zn = ZnCl₂ + H₂.

An acid salt is a compound derived from an acid which has not all of its hydrogen replaced, e.g., 2NaCl + H₂SO₄ = NaHSO₄ + HCl + NaCl.

(15) CHEMICAL NOMENCLATURE.--Termination “--UM” is now applied to all Metals, though the older-known metals retain the former names, e.g.--Aluminium, Tellurium, etc.

Termination “--IDE” denotes a Binary Compound, that is, a substance composed of only two elements, e.g., Sodium Chloride (NaCl).

Termination “--OUS” is applied to the first of two elements when it exists in a greater proportion than in another combination with the same element, e.g., one atom of phosphorus and three atoms of chlorine form Phosphorous Chloride.

Termination “--IC,” when the first exists in a lesser proportion, e.g., one atom of phosphorus with five atoms of chlorine form Phosphoric Chloride.

Prefixes “MONO--,” “BI--,” “TRI--,” etc., indicate the proportion of the latter of two elements, and are sometimes used instead of the above termination. Thus phosphorous chloride may also be called Phosphorous Tri-Chloride; so one atom of carbon with one atom of oxygen is Carbon Monoxide.

Prefix “HYPO--” (under) and “PER--” (over), specify compounds formed by the same two elements containing less (or more) of an element than is in the usual compound.

Nomenclature of Salts.--From the common acids we get the following salts:--

HCl forms chlorides. HNO₃ forms nitrates. H₂SO₄ forms sulphates. H₂S forms sulphides. H₂CO₃ forms carbonates. H₂O forms no salts. H₂SiO₄ forms silicates. H₃PO₄ forms phosphates.

A rough rule for the nomenclature of acids may be made from the above. Acids with the prefix hydro and the suffix ic form salts in ide; with suffix ate, salts in ate; with suffix ous, salts in ite.

(16) BASICITY.--The basicity of a substance is measured by the amount of hydrogen which it contains that can be replaced by a basic radical, e.g., H₂SO₄ is di-basic, i.e., the two atoms of hydrogen can be replaced by a basic radical. H₂SO₄ + CaCl₂ = CaSO₄ + 2HCl.

(17) QUANTIVALENCE.--The quantivalence of an element is measured by the number of atoms of hydrogen it combines with or replaces. E.g., Na is univalent, for when added to HCl it replaces one atom of hydrogen; Ca is bivalent, for, as seen in the above reaction, it replaces two atoms of hydrogen.

(18) TEST FOR A CHLORIDE.--To test for HCl or any chloride, add to the solution to be tested a little AgNO₃, and if a chloride is present, a milky-white precipitate will be formed. The reaction is as follows: HCl + AgNO₃ = AgCl (white precipitate) + HNO₃. A metal almost invariably changes places with hydrogen.

Caution.--In diluting H₂SO₄ add the acid to the water; for the evolution of heat from the process will cause the water to boil, and reversing this process will cause the liquid to boil over and possibly result disastrously.

(19) IMPURITY IN H₂SO₄.--Commercial sulphuric acid contains PbSO₄ as an impurity. This gives it the colored appearance, plumbic sulphate being soluble in strong sulphuric acid.

(20) H₂S.--Sulphuretted hydrogen is somewhat soluble in water, slightly poisonous, and is a reducing agent.

(21) CARBONIC ACID.--H₂CO₃ does not exist as an acid. We infer its existence from the presence of its salts. Na₂CO₃ + 2HCl = 2NaCl + H₂CO₃, but the H₂CO₃ is so unstable that it breaks up at once into H₂O and CO₂.

(22) TEST FOR A CARBONATE.--To test for a carbonate, treat the substance with an acid; CO₂ is formed; pour the gas into a solution of lime-water, and a white insoluble precipitate is formed, CaCO₃.

=TABLE OF ALL THE KNOWN CHEMICAL ELEMENTS=

The Chemical Elements are the simplest known constituents of all compound substances. Chemists regard them as elements or elementary substances only when they have been proved to be not compound. The elements are somewhat arbitrarily divided into metals and non-metals, the former constituting by far the larger class. Several elements occupy positions on the border line. Below is a list of the elements at present known with certainty, and of their atomic weights as fixed by the various kinds of evidence obtained by very numerous, and in many cases varied, experiments. The values are all referred to oxygen as standard with atomic weight 16, and are those adopted, for 1910, by the International Commission on Atomic Weights. The standard O = 16 has been pretty generally adopted by chemists as, upon the whole, more satisfactory than H = 1.

=Abbreviations.=--At. wt., atomic weight; S. G., specific gravity; M. P., melting point; B. P., boiling point; C. T., critical temperature.

CHEMISTRY OF THINGS FAMILIAR

WHAT IS STARCH? -- HOW MANUFACTURED? -- COMPOSITION OF WHEAT FLOUR -- ACIDS -- ALKALIES -- SULPHURIC, NITRIC, AND MURIATIC ACIDS -- SULPHURETTED HYDROGEN -- TANNING OF HIDES TO FORM LEATHER -- VINEGAR -- ALCOHOL -- YEAST -- FRUIT, HOW PRESERVED -- DECAY IN WOOD -- WHAT IS ETHER? -- DISINFECTING AGENTS -- HOW SMOKING PRESERVES MEAT -- WHAT IS ALBUMEN? -- WHAT IS A POISON? -- ARSENIC -- CERTAINTY OF ITS DETECTION -- LEAD PIPES, HOW POISON WATER -- VERDIGRIS -- CALOMEL -- PRESERVATION OF WOOD -- COMMON NAMES OF CHEMICALS

What is starch?

The name starch is given to a mealy substance which is deposited in most vegetables at the time of ripening, from the juices with which the cells of the plants are filled.

What common vegetable especially abounds in starch?

The potato, which consists entirely of cells filled with starch and water.

A cell is a little membranous bladder filled with a solid or fluid substance.

Why does a laundress find it necessary to boil starch before using it for stiffening linen, etc.?

The starch, consisting of little granules, is insoluble in cold water; but when acted upon by hot water, the granules burst and allow their contents, which are soluble, to become mingled with the water.

Starch is manufactured as follows:--

Potatoes, for example, from which most of the starch of commerce is manufactured, after being pared, are grated to a pulp. This pulp is put upon a sieve and stirred about, while at the same time a little stream of water is made to flow upon it. A milky liquid runs through the sieve, but the fibrous portion of the potato, the vegetable tissue, remains behind. This liquid, after a short interval, deposits a white powder, which is the starch. By the simple process of tearing up the vegetable tissue, and removing the inclosed starch by washing, this substance may be procured from a great variety of plants.

Why do potatoes, beans, rice, and most of the common vegetables, swell up when boiled with water?

Because the starch absorbs water at the boiling temperature, which causes the cells to swell, thereby giving to the vegetable a rounded appearance.

What is the composition of wheat flour?

Starch is one of the principal constituents of wheat flour, as well as of all other kinds of meal. The other principal constituent is a gray, tough, viscous substance, called gluten.

To what does paste, made of wheat or rye flour, owe its adhesiveness?

In some measure to the starch, but principally to the gluten contained in it.

Can starch be converted into gum and sugar?

It can; fruits and plants effect this change naturally: we can also produce the change artificially by chemical processes.

Why are potatoes frozen and thawed sweet?

Because by the freezing action the starch of the potato is in part converted into sugar.

Why are apples, pears, grapes, etc., in their unripe state sour, and in their ripe condition sweet?

In the unripe fruits mentioned starch is present; in the ripe fruits it is absent; in the process of ripening the starch is converted into sugar, and the fruit becomes sweet.

What are acids?

Acids are substances which excite the taste of sourness when applied to the tongue; they change the blue juices of vegetables to red, and combine with alkalies to form neutral compounds.

What is an alkali?

An alkali is a body that possesses properties the converse of those of an acid. It has a highly bitter, acrid taste, changes the blue juices of vegetables to green, or the juices of vegetables which have been changed red by an acid, back again to blue. Potash and soda are the representatives of the alkalies.

When sulphur is burned in the air what is the product formed?

Sulphurous acid.

What causes the suffocating odor of a lighted brimstone match?

The sulphurous acid generated by the combustion of the sulphur.

What is sulphuric acid or oil of vitriol?

It is a compound of sulphur and oxygen, containing one-third more oxygen than sulphurous acid.

What is sulphuretted hydrogen?

A gas formed by the union of sulphur and hydrogen. It possesses an offensive odor, and is very poisonous.

How is sulphuretted hydrogen formed in nature?

Principally from the decomposition of animal substances, as blood, flesh, hair, etc.

Why does the yolk of an egg tarnish a silver spoon?

Because it contains a little sulphur, which, at the temperature of an egg just boiled, will decompose the water or moisture upon the spoon, and produce sulphuretted hydrogen gas, which will tarnish silver.

Both the white and the yolk contain sulphur, but the latter the most abundantly.

What is it that makes an open or foul sewer so destructive of health to any district in which it may be situated?

The evolution of sulphuretted hydrogen. When inhaled, it acts directly upon the blood, thickening it, and turning it black.

Why do surfaces painted with lead paints, in the vicinity of sewers, soon turn black, or become discolored?

Through the action of sulphuretted hydrogen.

What is nitric acid?

Nitric acid, or aqua-fortis, is a compound of five parts of oxygen and one of nitrogen.

It is liquid; when pure, colorless, and highly corrosive; it attacks almost all dead, unorganized substances, and destroys living tissues.

What is muriatic, or, more properly, hydrochloric acid?

A compound of hydrogen and chlorine usually prepared from salt. It is an acid much used in the arts.

What is “lunar caustic”?

A compound of nitric acid and oxide of silver.

Why, when lunar caustic is applied to the flesh, does it burn and destroy it?

Through the agency of the nitric acid contained in it.

Do plants produce acids?

Acids are formed in the vegetable kingdom in great abundance; they especially exist in unripe fruits, imparting to them a sour taste.

Acids formed from mineral substances are called “mineral acids”; acids formed by or from vegetable substances are called “organic acids.”

Why does tanning hides convert them into leather?

Hides are steeped in water, with ground bark of the oak, hemlock, or other trees; these barks contain large quantities of tannic acid, which combine with the skin of animals, and form a combination which is insoluble in water and not subject to putrefaction--viz., leather.

What is ordinary vinegar?

An acid, called acetic acid, and water.

If wine or beer be imperfectly corked, why does it rapidly turn sour?

Because air gets into the liquor, and the oxygen of the air combining with the alcohol of the liquor produces acetic acid, or vinegar.

What is alcohol?

Alcohol is the spirit existing in wine, beer, cider, etc., obtained in the process of fermentation.

What is a ferment?

A ferment is a substance containing nitrogen in a state of decomposition, which is able to excite fermentation in solutions of sugar; old cheese, putrefying flesh, blood, etc., all of them are ferments.

What is yeast?

We apply the term yeast to a particular species of ferment; the foam of beer (or of some similar liquor), produced by fermentation.

Can you explain why it is that a body in a state of fermentation or putrefaction should cause unlimited quantities of similar matter to pass into the same state?

We only know the fact: the reason we are ignorant of. The most minute portion of milk, paste, juice of grapes, flesh, or blood, in a state of fermentation or putrefaction, causes fresh milk, paste, grape juice, flesh, or blood, to pass into the same condition, when in contact with them.

In storing or packing fruit for future use why is it necessary to carefully remove every decayed specimen?

Because the decayed portions of one specimen will quickly communicate decay to the fresh fruit in contact with it, and soon the whole mass of fruit will become putrescent.

If in a vessel, or any other structure, one timber becomes decayed what course ought to be adopted?

It should be removed immediately, or the decomposition once commenced will in time affect the whole structure.

It sometimes happens that physicians, in dissection, are seriously poisoned by the slightest cut of a knife which has been used upon the dead body. The knife introduces to the healthy blood, through the wound, a minute portion of matter in the state of decomposition or putrefaction. This acts as a ferment, and causes the healthy matter in contact with it to pass into the same decomposed state. The action once commenced rapidly extends, until the whole body becomes affected, and death ensues. It is almost impossible to heal wounds of this character.

Why is it especially dangerous to eat fruit or meats partially decayed?

Because the decayed portions of the substance eaten are liable to induce the same condition in the healthy organs of the stomach with which they may come in contact.

Why do fruit preserves frequently turn sour?

Because, owing to the action of some fermenting substance present either in the fruits themselves or in the air, the sugar used in preserving is converted into alcohol, and the alcohol into vinegar.

Why does the housewife scald her preserved fruits to prevent their turning sour?

Because fermenting substances and fermenting action are destroyed by a boiling temperature.

Why do we keep preserves, beer, cider, or other substances liable to turn sour, in a cool place?

Because a depression of temperature arrests fermentation, though it does not prevent its renewal when the temperature in increased.

What is ether?

Ether is a product obtained by distilling strong alcohol and sulphuric acid. The product is called sulphuric ether, but it does not contain sulphuric acid, nor has it any sulphur in its composition.

What are the properties of ether?

It is an exceedingly volatile, inflammable body, producing insensibility when inhaled, and readily dissolving all fatty and oily bodies.

Why will ether remove spots of oil, paint, or grease from garments?

Because it is a solvent for all greasy, oily matters.

What are the best agents for depriving putrid and decaying animal and vegetable substances of their offensive odors?

Chloride of lime is the most effectual agent; and chloride of zinc and sulphate of iron (green vitriol) are also exceedingly efficient. On a large scale, as in the sanatory cleansing of towns, pulverized charcoal, burnt clay, and quicklime are to be recommended.

What effect does the use of perfumes or the burning of pastiles have upon offensive odors?

They merely disguise the odor, but do not remove or destroy it.

By adopting what precautions may a person safely enter sick rooms, or visit, without risk, the most dangerous receptacles of filth?

By moistening a linen cloth with vinegar, and sprinkling over it finely-powdered chloride of lime.

Air breathed through this, applied to the mouth and nostrils, will enter the lungs charged with a minute quantity of chlorine, which will effectually destroy any noxious vapors or miasms that escape from diseased bodies, or from decaying animal and vegetable substances.

What three conditions are requisite to produce putrefaction in animal and vegetable substances?

It is necessary that they should be exposed to the combined influence of air, heat, and moisture.

Why is a substance preserved from decay by drying, or by the exclusion of air from it?

Because by so doing we remove the moisture and air essential to the process of decay.

Why does the smoking of fish or flesh contribute to their preservation?

Because the volatile matters of the smoke, such as creosote, pyroligneous acid, and the like, effect a species of chemical combination with the fiber of the meat, and with the substances contained in the natural juices of the flesh, which combinations are less liable to decay than the substances themselves.

What is albumen?

Albumen is an animal substance as well as vegetable. It exists most abundantly, and in its purest natural state, in the white of an egg, from whence it derives its name (album ovi), which is the Latin for the white of an egg.

The serum or fluid portion of the blood (which, after exposure to the air, is separated from the more solid part), the vitreous and crystalline humors of the eye, the brain, the spinal marrow, and nerves, all contain albumen.

What is the yolk of an egg?

This also consists of albumen, but contains in addition a yellow oil, which imparts to it its color.

Why is meat tough which has been boiled too long?

Because the albumen becomes hard, like the white of a hard-boiled egg.

The best way of boiling meat to make it tender is this: Put your joint in very brisk boiling water; after a few minutes add a little cold water. The boiling water will fix the albumen, which will prevent the water from soaking into the meat, keep all its juices in, and prevent the muscular fiber from contracting. The addition of cold water will secure the cooking of the inside of the meat, as well as of the surface.

Why is meat always tough if it be put into the boiler before the water boils?

Because the water is not hot enough to coagulate the albumen between the muscular fibers of the meat, which therefore runs into the water, and rises to the surface as scum.

Why is the flesh of old animals tough?

Because it contains very little albumen, and much muscular fiber.

What is a poison?

A poison is any agent capable of producing a dangerous effect upon anything endowed with life.

In cases of poisoning by substances taken into the stomach, what course should be pursued, in the absence of medical attendance?

The first step is to evacuate the stomach by means of powerful emetics, and when vomiting has taken place, warm water and the white of eggs may almost always be given with advantage.

Can poisons administered for criminal purposes be almost certainly detected?

They can; chemical science within the last few years has made such advances that the most minute quantities of all the best known poisons can be detected with certainty long after death.

There is no poison so liable and certain to be found as arsenic, and in almost every case of poisoning with mineral poisons, science is enabled to detect the substance, even when life has been extinct for years, and the body nearly decomposed.

What is arsenic?

Metallic arsenic is an exceedingly brittle metal, of a steel-gray color. It vaporizes, when heated, with a strong odor of garlic, a property not possessed by any other metal.

The substance used as poison, and sometimes known as ratsbane, is arsenious acid, a compound of arsenic and oxygen. Arsenious acid has the form and appearance of a fine white powder.

What is the best remedy in cases of poisoning with arsenic?

The hydrated peroxide of iron (iron rust) is considered the best remedy.

The following is the best method for preparing this substance: Take common copperas (sulphate of iron) four ounces; dissolve in warm water in a glass, or porcelain dish, and add a small quantity of sulphuric acid, and afterwards ammonia solution, so long as a dense red precipitate is formed. This precipitate carefully strained off, and thoroughly washed in a filter with water, is hydrated peroxide of iron. So long as kept moist, it may be preserved for a great length of time.

Is lead a poison?

Lead and nearly all its compounds are dangerous and secret poisons; when received into the system, it frequently remains dormant for years, and then suddenly manifests itself in various forms of disease.

What is the disease called “painter’s colic”?

A disease to which painters and others working in lead are liable, in consequence of receiving into their system, imperceptibly, portions of lead.

Is it dangerous to sleep in, or breathe the air of, a room newly painted with paints containing lead?

It is highly dangerous, since the air is filled with a vapor of the lead compound used as paint.

Why are some waters, when conveyed through lead pipe, poisonous?

Waters which are very pure and contain much oxygen dissolved in them; waters which contain nitric acid compounds, such as those flowing from the vicinity of barn-yards, manure heaps, and those which contain common salt or organic matter, as water flowing from swamps and fields; waters containing soluble carbonates--all dissolve lead from the pipes through which they may be made to pass. Constant use of such waters, in the process of time, will introduce sufficient lead into the system to produce disease, which is often attributed to other causes.

What is verdigris?

Verdigris is a compound of copper, oxygen, and acetic acid. This, and all the compounds of copper, are very poisonous. The most efficacious antidotes for poisoning with copper are white of eggs and milk.

What is calomel?

It is a compound of two parts of mercury united to one of chlorine, forming the sub-chloride of mercury. The preparation, commonly known in medicine as “blue pill,” is a preparation of calomel.

What is corrosive sublimate?

A compound of mercury and chlorine united in equal proportions, forming the perchloride of mercury.

Are both these compounds, calomel and corrosive sublimate, poisons?

They are; corrosive sublimate, especially, is a most deadly poison. In case of poisoning by it, the most effectual antidote is white of eggs.

What is the process of preserving wood from decay, commonly termed “kyanizing”?

It consists in saturating the fibers of the wood with a solution of corrosive sublimate.

Poisonous substances, and corrosive sublimate especially, have the property of protecting animal and vegetable substances from decay. The skins of stuffed birds and animals, and the plants of a herbarium, may be protected from insects and decay, by washing them with a solution of corrosive sublimate. It should not, however, be forgotten that these substances by such treatment become themselves poisonous.

Give a list of the chief antidotes for poisons.

(See Book of the Human Body.)

What are the common names of familiar chemical substances?

COMMON NAMES OF CHEMICALS

Common Names Chemical Names and Formulæ

Alum Sulphate of Aluminum and Potassium Aqua Fortis Nitric Acid, HNO₃ Aqua Regia Nitro-Hydrochloric Acid Calomel Mercurous Chloride, Hg₂Cl₂ Carbolic Acid Phenol, C₆H₅OH Caustic Potash Potassium Hydrate, KOH Caustic Soda Sodium Hydrate, NaOH Chalk Calcium Carbonate, CaCO₃ Copperas Sulphate of Iron Corrosive Sublimate Mercuric Chloride, HgCl₂ Cream of Tartar Potassium Bitartrate Epsom Salts Magnesium Sulphate Ether Diethyl Oxide, (C₂H₅)₂O Fire Damp Light Carburetted Hydrogen Galena Lead Sulphide, PbS Glauber’s Salt Sodium Sulphate Glucose of Grape Sugar Dextrose, C₆H₁₂O₆ Goulard Water Basic Acetate of Lead Iron Pyrites Iron Di-Sulphide, FeS₂ Jewelers’ Putty Oxide of Tin Laughing Gas Nitrous Oxide, N₂O Lime Calcium Oxide, CaO Lunar Caustic Silver Nitrate, AgNO₃ Mosaic Gold Bi-Sulphide of Tin Muriatic Acid Hydrochloric Acid, HCl Olefiant Gas Ethylene, C₂H₄ Plaster of Paris Calcium Sulphate Quartz Silicon Dioxide, SiO₂ Realgar Arsenic Di-Sulphide, As₂S₂ Red Lead Oxide of Lead, Pb₃O₄ Rochelle Salt Sodium Potassium Tartrate Salammoniac Ammonium Chloride Salt, Common Sodium Chloride, NaCl Salt of Tartar Potassium Carbonate Saltpeter Potassium Nitrate, KNO₃ Salts of Lemon Oxalic Acid Slaked Lime Calcium Hydrate Soda Sodium Carbonate Spelter Zinc Spirits of Hartshorn Amm. Hydroxide, NH₄OH Spirits of Salt Hydrochloric Acid, HCl Sugar of Lead Lead Acetate Tartar Emetic Potass. Antimony Tartrate Verdigris Basic Copper Acetate Vermilion Sulphide of Mercury Vinegar Dilute Acetic Acid Vitriol, Blue Copper Sulphate Vitriol, Green Ferrous Sulphate Vitriol, Oil of Sulphuric Acid, H₂SO₄ Vitriol, White Zinc Sulphate Volatile Alkali Ammonia

What is meant by radio-activity and radio-active substances?

Radio-activity is the phenomenon associated with substances which spontaneously emit rays of unique penetrating power through the escape of electrons and their striking against other substances. Chief of the radio-active substances are radium, polonium, actinium, thorium, etc.

What is the history of these substances?

Henri Becquerel in 1896 first observed this in the case of potassium uranyl sulphate, the rays from which he found affected a photographic plate through black paper, thin plates of metal, etc.; the property was further traced in other uranium salts and in uranium itself. These rays are known as Becquerel rays, and have the further power to render air a conductor of electricity, and thus to discharge any electrified substance placed near them.

A charged electroscope forms a test of radioactivity, and the rate at which the leaves fall measures the degree. Different uranium salts have different degrees of radio-activity; some varieties of pitchblende, as also chalcolite, show the property in excess of uranium contained.

Madame Curie, by using the activity test for every precipitate obtained from pitchblende, succeeded in discovering the elements polonium and radium in 1898. The next year Debierne discovered actinium, another radio-active element in the same substance. Meanwhile Schmidt and Madame Curie independently found that the same properties were associated with thorium, its compounds and the minerals containing it. In 1903 Ramsay and Soddy discovered that radium continuously produces helium, the lightest of the inactive gases discovered by Ramsay in 1896.

Twenty-eight elements are now classed in three divisions with the three parents, uranium, thorium, and actinium. Potassium and rubidium have been shown to be radio-active, but otherwise the alkaline metals do not enter the classes.

Describe radium and its special properties.

WHAT IT IS LIKE.--To the eye a tiny sample of radium--or, to speak more correctly, of one of the radium salts, for radium in a pure state (i.e. the metal) has not been obtained as yet--presents no very striking appearance. All one sees is a few tiny crystals, or perhaps a few specks of whitish-looking powder, glowing in the dark with a faint phosphorescent light similar to that sometimes emitted by a piece of decaying fish.

THE RADIATIONS are of three kinds, comparable with those of the vacuum tube: Alpha-rays are heavy particles, positively charged, similar to the canal rays; Beta-electrons, negative like cathode rays; Gamma-rays resemble Röntgen rays. They penetrate matter to different degrees, behave differently under the action of a magnetic field, but under ordinary circumstances travel in straight lines.

But rays from different elements vary in penetration, and also with the absorbing substance, varying roughly with the density.

The Alpha-rays have a velocity of from 1.56 × 10₉ centimeters per second (radium) to 2.25 × 10₉ centimeters per second (thorium); they are particles of helium carrying a double charge of electricity. Beta-rays have a greater range of velocity and approach that of light. Both Alpha- and Beta-rays are absorbed by a thickness of one centimeter of lead, but Gamma-rays pass through an inch of lead; they carry no charge of electricity, yet ionize the air and discharge the electrometer.

All the rays on impinging on solid particles give rise to secondary rays, sometimes called Delta-rays, electrons moving with comparatively low velocity. The Alpha-rays possess ninety-five per cent of the energy evolved and produce brilliant fluorescence in zinc sulphide, diamond, etc., the other rays producing this best in willemite and the platino-cyanides; all become absorbed and transmuted into heat.

Radium every hour generates sufficient heat to raise its own weight of water from freezing to boiling point.

THE SPINTHARISCOPE.--This is a simple piece of apparatus invented by Sir William Crookes, by means of which some of the effects of the Alpha-ray particles can be observed in a very striking manner. It consists of a little screen covered with powdered zinc sulphide. A small fragment of radium is placed directly in front of the middle of the screen and in close proximity to it. On observing this screen in the dark through a suitable lens, scintillating little points of light are seen to be continually flashing into view and dying away. Each tiny spark is thought to be produced by the impact of a single Alpha-ray particle. That these particles or emanations must be matter in a state of extreme attenuation is proved by an experiment of Professor Curie’s in which a box constructed of platinum was pierced with two holes so minute as to be capable of retaining a vacuum, and yet these radium emanations passed through quite freely.

What are the medical uses of radium?

Ulcerous growths, birth-marks, and scars are beneficially treated, but so far the selective action of radium on tissue has not been determined, nor its bactericidal effect. Its results in the treatment of cancer have not yet reached a definite stage, though it has been widely heralded as a specific for that dreadful malady.

The application of the rays is by various methods: inhalation of the emanation; external application or injection of the emanation condensed on glycerine, vaseline, oil, water, etc.; or the taking of quinine, arsenic, bismuth, etc., on which the emanation has been condensed. Injections of very dilute solutions of radium salts, or insoluble salts suspended in water, are made. But external applications of the rays are considered most important; copper plates or linen are coated with varnish containing the salts, or glass tubes contain them, and the radiations are directly applied, the surrounding parts being protected with lead foil.

HOW TO READ A GAS METER

The dial marked “1 thousand” in the accompanying illustration is divided into hundreds; the dial marked “10 thousand” is divided into thousands; that marked “100 thousand” into ten-thousands, and that marked “1 million” into hundred-thousands. When 1,000 cubic feet of gas have been consumed, the pointer on the dial marked “1 thousand” will have made a complete rotation and the fact will be indicated by the pointer of the next dial at the left, which will point to the figure 1. When 10,000 cubic feet of gas have been consumed, the pointer on the “10 thousand” dial will point to 1, and so on. In reading a gas meter, put down the hundreds first, then the thousands, and so on, always counting the figure just under, or which has just been passed by, the pointer. In the illustration about half a hundred is indicated on the “1 thousand” dial, three thousands is indicated on the next dial, two ten-thousands on the next dial, and one one-hundred-thousand on the “1 million” dial. The reading will be 123,050. The dial marked “ten feet” is called the units dial. It is used for testing the meter to discover whether it is in working order or not. Each mark represents a cubic foot and the complete circle 10 cubic feet. If the pointer moves when no gas is burning, it indicates a leak. If it does not move when the gas is burning, or if its motion is unsteady, it indicates a derangement in the mechanism and shows that the meter requires attention.

=OUTLINE COURSE OF ELEMENTARY SCIENCE FOR THE GRADES=

======+=========================================+===================== GRADES| LIFE | STRUCTURE ------+--------------------+--------------------+--------------------+ | ZOOLOGY | BOTANY | MINERALOGY | | | | | ------+--------------------+--------------------+--------------------+ I.|Observe-- |Observe-- |Observe | II.|1. Birds; migration,|1. Flowers; color, |1. Pebbles and | III.|nesting, feeding. |form, parts. |rocks; color, shape,| |2. Insects; butter- |2. Fruits; color, |hardness. | |flies, moths, earth-|form, etc. |2. Kinds of rock; | |worms. |3. Leaves; shape, |quartzose, calcites.| |3. Uses of birds and|color, veining. |3. Uses; for soil | |insects. |4. Stems; form, po- |making and building.| | |sition, bark, struc-| | | |ture. | | | |5. Conditions of | | | |growth, habits, etc.| | | | | | ------+--------------------+--------------------+--------------------+ IV.|By observing the |Observe characteris-|1. Sandstone | |form and structure, |tics of-- |2. Argillaceous | |determine some |1. Exogens and |rocks. | |1. Orders of mam- |Endogens. |3. Formation of | |mals. |2. Kinds of trees, |rocks. | |2. Orders of birds. |fruits, vegetables, | a. Sedimentary; | |3. Orders of |grasses and grains. | sandstone, lime- | |insects. |3. Effects of culti-| stone, etc. | |4. Orders of rep- |vation. | b. Igneous; | |tiles. | | granite, etc. | |Uses of animals. | | | | | | | ------+--------------------+--------------------+--------------------+ V.|Characteristics, |Observe characteris-|Formation and uses--| |habits and uses of--|tics-- |1. Coal. | |1. Fishes. |1. Plants of the |2. Mineral oils. | |2. Oysters, crabs, |rose, pine, pulse, |3. Natural gas. | |starfishes. |violet, pink, mus- |4. Iron; ores. | |3. Coral animals. |tard, composite, | | | |lily, grass and fern| | | |families. | | | | | | | | | | | | | | | | | | | | | | ------+--------------------+--------------------+--------------------+ VI.|Characteristics of |Peculiarities, |1. Minerals and | |Animals of the-- |habits, uses-- |mines of the United | |1. Temperate cli- |1. Palm, banana, |States. | |mate. |pineapple and orchid|2. Gold and silver. | |2. Tropical climate.|families. |3. Copper. | |3. Polar climate. |2. Mosses; lichens. | | |Uses made of them. | | | | | | | | | | | | | | | ------+--------------------+--------------------+--------------------+ VII.|Animals of the dif- |1. Zones of vegeta- |Mines and minerals | |ferent zones of the |tion. |of other countries. | |Old World compared |2. Limits of migra- | | |with those of the |tion. | | |United States. Dis- |3. Vegetable pro- | | |tribution and migra-|ducts of commerce. | | |tion; cause; limits.| | | | | | | | | | | | | | | | | | | ------+--------------------+--------------------+--------------------+ VIII.|Relation of animal |1. Culture of |Minerals. | |life to vegetation |fruits, vegetables, |1. Constituents. | |and civilization. |fibers, grains. |2. Commercial value | |Checks on animal |2. Commercial value;|and uses in the | |life. |benefits to man. |arts, etc. | | | | | ------+--------------------+--------------------+--------------------+

======+============================================================== GRADES| STRUCTURE ------+--------------------+--------------------+-------------------- | GEOLOGY | PHYSICS AND | ASTRONOMY, | | CHEMISTRY | METEOROLOGY ------+--------------------+--------------------+-------------------- I.|Rain; its effects-- |Observe qualities; |Observe-- II.|1. On the surface; |elastic, porous, |1. Sun, moon, con- III.|slopes, ponds, in |etc. |stellations. |valleys, streams. |1. Forms of water; |2. Wind, clouds, |2. Below the sur- |their uses. |rain, snow, frost, |face; springs, cav- |2. Atmosphere; |dew. |erns, etc. |weight, composition.|3. Their causes. |River Basins-- |3. Magnetism; elec- |4. Effects. |1. Boundary, uses, |tricity. | |etc. |4. Solutions. | |2. Alluvial de- |5. Gases; hydrogen, | |posits. |oxygen, nitrogen, | | |carbonic acid gas. | ------+--------------------+--------------------+-------------------- IV.|1. Ocean; effects of|1. Heat; sources: |Climate; causes: |waves, tides, |sun, fuel, friction.|1. Winds, direction |currents. |2. Transmission; |of sun’s rays. |2. Glaciers; mo- |conduction, radia- |2. Surface; moun- |raines: formation, |tion, convection. |tains, vegetation. |effects. |3. Uses: warming, |3. Bodies of water; |3. Volcanoes; gey- |cooking, smelting. |rivers, ocean |sers; earthquakes. |4. Physical and |currents. |4. Gradual elevation|chemical changes |Twilight; duration. |and depression of |observed. | |the earth’s crust. |5. Carbon; forms; | | |uses. | ------+--------------------+--------------------+-------------------- V.|Continent building--|1. Light-- |1. Prevailing winds. |1. Mountains, | a. Sources; |2. U. S. weather |plains, coast lines.| uses. |maps. |2. Agencies; | b. Transmission,|3. Climate of the | a. Vegetable; | reflection, re- |United States. | peat-bogs, swamps.| fraction. | | b. Animal; coral| c. Lenses, | | formation, shell | glasses. | | deposits. |2. Fermentation of | | c. Chemical |fruit juices; yeast.| | springs, geysers, | | | caverns, deposits | | |in lakes and seas. | | ------+--------------------+--------------------+-------------------- VI.|1. Appalachian and |1. Magnetism; uses: |North and South |Rocky mountains. |compass, electro- |America-- |2. River basins and |magnets. |1. Winds; trades, |great lakes of the |2. Electricity; |polar, variable. |United States. |sources and uses. |2. Wind zones. | |3. The levers; |3. Weather maps. | |scales. | | |4. Equilibrium of | | |bodies. | | |5. Chlorine. | ------+--------------------+--------------------+-------------------- VII.|Continent struc- |Pendulum; inertia, |Trades and Monsoons. |ture-- |motion. |1. Deserts; Sahara, |1. South America. |Forces: gravitation,|Arabia, etc. |2. Eurasia. |cohesion, chemical |2. Heavy rains of |3. Australia. |attraction. |India. |4. Africa. |Capillary attrac- | | |tion; osmose pres- | | |sure and flow of | | |liquids. Testing air| | |and water for | | |impurities. | ------+--------------------+--------------------+-------------------- VIII.|The earth; form, |Sound; propagation, |The Solar system. |crust-- |reflection, vibra- |The moon. |1. Rock strata; |tion, music. |The sun; fixed |fossils. |Examination of |stars. |2. Geological ages. |soils. |The tides; ocean | | |currents. ------+--------------------+--------------------+--------------------

SOME GREAT MECHANICAL INVENTIONS

STEAM ENGINES

What are steam engines?

Steam engines are machines in which the elastic force of steam is used as a motive power. In the ordinary engines the alternate expansion and condensation of steam imparts to a piston an alternating rectilinear motion, which is changed into a circular motion by means of various mechanical arrangements.

The engine is unquestionably the grandest and most influential for good of all the great inventions in the realm of physics. No other contrivance of man can be compared with this gigantic, yet tractable motor, in relieving both man and beast of ceaseless toil and irksome drudgery; in preventing suffering and starvation, and promoting intercourse, progress and civilization among the nations of the earth.

Give a description of the steam engine.

Every steam engine consists essentially of two distinct parts: the apparatus in which the steam is produced, and the engine proper. We shall first describe the former.

STEAM BOILER.--The boiler is the apparatus in which steam is generated. Usually a cylindrical boiler is used for fixed engines; those of locomotives and of steam vessels are very different.

The steam is produced from water at a pressure considerably above that of the atmosphere, and is delivered to the engine with as little loss of pressure and heat as possible. The higher the pressure of the steam, the greater will be the amount of heat available, in a given weight of steam, for conversion into mechanical energy. Only a fraction of the total heat energy given to the steam in the boiler is converted into the mechanical work in the engine. By far the greater portion still remains in the steam after it has passed through the engine. The proportion of heat utilized depends on the thermal efficiency of the engine, amounting from twelve to fifteen per cent in good condensing engines; in the very best engines of large size it may be as high as twenty per cent.

The terms axis, axle, arbor, and shaft, in mechanics, are generally understood to mean the bar, or rod, which passes through the center of a wheel. A gudgeon is the pin, or support, on which a horizontal shaft turns; the pins upon which an upright shaft turns are called pivots.

The engine proper consists of a hollow cylinder closed at both ends; inside it is the piston, a sliding partition which fits the bore of the cylinder sufficiently close to prevent the steam leaking past it, but having sufficient freedom to allow it to move from end to end of the cylinder with as little friction as possible.

In modern engines the pressure of the atmosphere is not employed to drive the piston down. The steam is admitted into the cylinder above the piston at the same time that it is condensed or withdrawn from below, and thus exerts its expansive force in the returning as well as in the ascending stroke. This results in a great increase of power.

The practical construction of the piston and cylinder, and the arrangement of connecting pipes by which steam is admitted alternately above and below the piston, is fully shown in Figure A. This gives a sectional view of the cylinder, of the piston, and of the distribution of steam. The entire engine is of iron. To the piston, T, is fixed a rod, A, which slides with gentle friction in a tubulure, U, placed at the center of the plate which closes the cylinder. As it is very important that no steam shall escape between the piston-rod and this tubulure, the latter is formed of two pieces, one attached to the plate, while the other, which fits in the first, can be pressed as tightly as is desired, so as to compress the material soaked with fat which is between the two tubulures. This arrangement is called a stuffing-box; it prevents the escape of steam without interfering with the motion of the piston.

VALVE-CHEST.--This is the arrangement by which steam passes alternately above and below the piston.

Figure A presents a vertical section of this valve-chest and shows its relation to the cylinder. The steam enters the valve-chest from the boiler by the brass tube x. From the valve-chest two conduits, a and b, are connected with the cylinder, one above and the other below. If they were both open at once, the steam, acting equally on the two faces of the piston, would keep it at rest. But one of these is always closed by a slide-valve, y, fixed to a rod, i. This moves alternately up and down, by means of an eccentric, e, placed on the horizontal shaft. The slide-valve closes the conduit a, and allowing the steam to enter at b, below the piston, the latter rises. But when it reaches the top of the stroke the rod i sinks, and with it the slide-valve, which then closes the conduit b, and allows the steam to enter at a. The piston then sinks, and so forth at each displacement of the slide-valve.

It now remains to explain what happens when the steam presses below the piston. It must not remain above, otherwise the piston could not move. But while the steam enters below by the conduit b, the top of the cylinder, by means of the conduit a, is connected with a cavity, O, from which passes the tube L. Through this tube the steam which has already acted upon the piston passes into the atmosphere, or else is condensed in a vessel filled with cold water, which is called the condenser. If, on the other hand, the piston sinks, the vapor below the piston passes, by the conduit b, to the cavity O, and to the tube L.

TRANSMISSION OF MOTION.--The alternating rectilinear motion thus generated within the cylinder is transmitted, by means of a rod attached to the piston, to a strong beam ff, movable upon a central axis, a system of jointed rods ee, called the parallel motion, being interposed for the purpose of neutralizing the disturbing action which the circular path of the beam would otherwise exert upon the piston. The reciprocating motion of the beam is now, through the intervention of the connecting-rod g and crank h, converted into a circular or rotatory motion, which is rendered continuous and uniform by the fly-wheel i, to the axis of which the machinery to be impelled is connected.

The air-pump, p, for withdrawing the vapor and water from the condenser, the feed-pump, s, for supplying the boilers, and cold-water pump, t, for supplying the condenser cistern, are all worked by rods from the beam; and the governor, u, for maintaining uniformity of motion, is driven by a band from the crankshaft. The above description refers more immediately to that class of steam engines called low-pressure engines.

TYPES OF ENGINES.--The various forms of the steam engine have received a varied form of classification. There are the general divisions into condensing and non-condensing engines, compound and non-compound, and single, double, or direct acting. Again there is the classification connected with the position of the cylinder, as in the horizontal, vertical, and inclined cylinder engines. Another classification divides steam engines into the uses to which they are applied, such as stationary engines, portable engines, marine, locomotive, electric generating, pumping, mill driving, winding, etc.

STEAM TURBINE.--The steam turbine, though the most modern form of the steam engine in practice, is the most ancient in actual history, the germ of the invention dating from Hero of Alexandria, in the second century B. C.

One kind of steam turbine is really worked on the same principle as a windmill, only steam is used instead of the wind. Instead, however, of the sails making one revolution in seven or eight seconds, it sometimes makes three thousand revolutions a minute, or fifty revolutions a second. In another kind the blades of the turbine are something like the pockets on a water-wheel, and the steam shoves the wheel round by its great velocity.

Turbine engines are now fitted to vessels of large dimensions, up to ocean liners and battleships, with extremely satisfactory results. Turbine engines have also been applied in various other ways, e.g., to the driving of fans and blowers.

The principle of internal combustion, as used in gas and oil engines, has also been applied to the turbine with marked success, and has done much to solve the all-important problem of efficiency. It is extremely improbable that the long-range activities of the submarine would be nearly so effective were it not for the application of the same principle to their engines.

LOCOMOTIVES

Locomotive engines, or simply locomotives, are steam engines which, mounted on a carriage, propel themselves by transmitting their motion to wheels.

The parallel motion, the beam, and the fly wheel of the ordinary stationary engine form no part of a locomotive. The principal parts are the framework, the fire box, the casing of the boiler, the smoke box, the steam cylinders, with their valves, the driving wheels, and the feed pump.

The framework rests on the axles of the wheels. The illustration on another page shows clearly the arrangement and parts of a typical locomotive. It will be observed that in the lower part of the steam dome is the fire box, from whence the flame and the products of combustion pass into the smoke box, and then into the chimney after having previously traversed the numerous brass fire tubes which pass through the boiler. The boiler, which connects the fire box with the smoke box, is made of iron, and is cylindrical.

The steam passes from the boiler into two cylinders, placed on either side of the smoke box. There, by means of a steam chest similar to that already described, it acts alternately on the two faces of the piston, the motion of which is transmitted to the axle of the large driving wheels. After having acted on the pistons, the steam is forced through the blast pipe into the chimney, thus increasing the draft.

The motion of the pistons is transmitted to the large driving wheels by two connecting rods, which, by means of cranks, connect the piston rods with the axles of the wheels. The alternating motion of the slide valve is effected by means of eccentrics placed on the axles of the large wheels.

WHEELS OF THE LOCOMOTIVE.--The wheels range ordinarily from forty-five to eighty-five inches in diameter for drivers, thirty to forty-two inches for truck wheels. They are made of castiron or steel body and steel rim shrunk on. Spoked wheels are usual for drivers, solid wheels for trucks. The tread is four to five inches wide, the flange (one to one and one-quarter inch high) increasing this to five and one-half to seven inches. A counterbalance weight is cast between the spokes opposite the crank-pin seat. The axles, forged steel, are six to eight inches in diameter (for drivers); the wheels are forced on their ends by a powerful press. Cranked axles (for inside cylinders) are forged to shape, rarely built up.

CONTROL.--The locomotive is controlled by the throttle-valve and the reverse lever. Both are located in the cab, which is built at the rear around the fire box, and serves also as firing platform.

AUXILIARIES.--The necessary auxiliaries of the locomotive are those required for its operation as a power generator, and those necessary to its service as a railroad vehicle or as a tractor. The tender is the most important in the first group. It is a separate vehicle attached behind the locomotive, carrying a water tank of three to eight or nine thousand gallons capacity, and a coal bin of two to ten tons capacity. Eight-wheel (two-truck) tenders are usual. The coal space is at the front of the tender, and the water tank occupies the rear half and extends forward along the sides of the coal bin. The coal thus is reached directly from the rear of the engine cab.

Water is supplied to the engine by pipes leading from the tank to injectors on the engine. Feed pumps are rarely used for pumping the water into the boiler, injectors in duplicate being depended on. The safety valve, mounted on the top of the boiler, is of the spring poppet type. A steam whistle is placed alongside, for use as warning and train-movement signal; a bell operated from the cab by a cord is also mounted on the boiler.

The air-brake equipment of the locomotive comprises the brake mechanism for the engine itself, and an air pump with its governor, a main reservoir, and the engineer’s valve, for supplying and manipulating the brakes of the entire train. The air pump is a direct-coupled compressor whose steam and air cylinders have a common piston-rod, attached in vertical position to the side of the boiler in front of the cab. The cylinder diameter is eight to ten inches. It pumps air into the main reservoir, a cylindrical tank hung under the boiler. An automatic pressure governor starts the compressor when the pressure falls and stops it when the full reservoir pressure is restored.

The locomotive brake equipment consist of brake cylinder and lever system connected to the wheel brake-shoes, but its valve control differs somewhat from that of a car, so as to permit braking the engine alone if desired. The engineer’s valve is a flat-seat rotary valve with positions for supplying brakes, recharging the train-pipe, and closing all connections. A separate valve is usually supplied to operate the engine brake alone, working this as “straight-air” or non-automatic brake. Reservoir and train-pipe gauges are mounted in the engine cab near the brake handles. Steam brakes are no longer fitted on American locomotives. The driving-wheels only of the locomotive are braked, but the tender is fully braked.

The sand-box for increasing the driving-wheel friction on wet or greasy rail is commonly set on top of the boiler with discharge pipes ending in front of the drivers just above the rail. A compressed-air ejector is now often used (pneumatic sander), in which case the sand-box may be placed on the front sill or in other convenient position with equal effectiveness.

THE CAB, with windows in front and sides, is built around the fire box, providing a seat on either side which commands a view ahead over the track. The reverse lever is placed on the right-hand, or engineer’s side, from where also the throttle lever and brake-valve handles are reached. Injector, whistle, sander, bell, drain cocks, traction-increaser, and other appliances are controlled from here. The headlight, set on top of the boiler in front of the stack, is usually an oil lamp, with parabolic reflector. Acetylene and electric headlights are extensively used in recent years, the latter supplied by a small steam-turbine and dynamo combination.

CLASSES AND TYPES OF LOCOMOTIVES.--The wheel-arrangement of a locomotive is, in conjunction with its total weight, the chief characteristic. Freight locomotives, running at slow speeds, utilize a large adhesion, and therefore have a large proportion of their weight carried on drivers; they have less need for good guiding quality and steadiness at great speeds. Passenger locomotives, working at high speeds, develop a much lower tractive force, and therefore require less weight on drivers, but need leading wheels for guiding quality and steadiness.

The number and arrangement of cylinders is another characteristic of classification. Most locomotives have two cylinders, both simple. Compounds are built with two, three or four cylinders.

RECENT DEVELOPMENTS.--The chief factor in the modern modification of locomotive types and details is increase of size. The only limiting factors are boiler capacity and weight on drivers.

Economy of operation has brought compounding into much favor even for single-frame engines, and more recently has led to the wide adoption of super-heating; these improvements also allow increased power to be obtained from a boiler of given size.

WEIGHT AND POWER.--Locomotives weighing seventy-five to one hundred and twenty-five tons (without tender) are common. In power, road locomotives range from three hundred to one thousand five hundred horse power and occasionally to two thousand horse power, the more modern ranging from seven hundred to one thousand five hundred. High-speed passenger locomotives are usually more powerful than heavier freights.

BOILER PERFORMANCE.--The distinguishing feature of the locomotive boiler is its high evaporative capacity, and the very high rates of fuel-burning. At full power one hundred pounds coal are burned per square foot of grate surface per hour, by virtue of the strong draft produced by the exhaust-steam blast. At moderate speeds twenty-five to forty pounds are burned.

ELECTRIC LOCOMOTIVES.--The operation of heavy railroad service (i.e. trains of freight cars and long passenger trains) by electric power requires the use of electric locomotives in place of the car-motor arrangement of street railroads. Such locomotives have been built since the middle of the nineties, and in considerable number since 1905. The earlier ones had the motors geared to the axles, or directly mounted thereon, but recent constructions have the motors mounted on the frame or platform, above the wheels, so that their weight is carried by the frame springs, and the motors drive the wheels through coupling-rods either direct or by way of an intermediate jack-shaft. This form is found to give smoother running and exert less destructive effect on the track than the prior forms. In wheel arrangement these locomotives vary greatly, but recent machines exhibit combinations of coupled drivers with leading and trailing trucks not unlike the arrangement of steam locomotives. Electric locomotives of two thousand to three thousand horse power have been built, and are in regular use hauling trunk-line trains.

AËROPLANES

Flying-machines are distinguished from balloons and dirigibles in being “heavier than air,” and consequently raised and supported by dynamic means alone, by the reaction of the air on surfaces driven through it.

Essentially, the aëroplane may be compared to a kite in which the pull of the string is replaced by the thrust of the propeller.

On December 17, 1903, the Brothers Wright, in America, made their first power-flight; while the very first public flight was made in France by Santos-Dumont on September 14, 1906.

Before it was possible to produce a power-driven aëroplane, experiments over a long course of years were made with aëroplanes not provided with propelling apparatus.

In its earliest form the aëroplane consisted of a flat surface moved through the air in a position slightly inclined from the horizontal; in its forward movement the plane experiences resistance from the air. As this resistance is directed partly on the under side, it will be partly converted into a lifting force. Of these two forces--head resistance or drift, and the lifting or sustaining force or lift--the first, being unproductive, must be reduced as far as possible; the second, lift, must, on the other hand, be raised to the highest possible degree.

This end is achieved by employing, instead of flat surfaces or planes, surfaces curved in the direction of flight.

THE TWO TYPES.--A monoplane is a machine with a single spread of surface supporting it. The best known example of a monoplane is the Bleriot. Biplanes have two supporting surfaces, the one above the other; the Wright and Farman machines are machines of this type. There are other machines which have been invented which have more supporting surfaces than this, the most successful of them all being the Roe triplane. But at present, at any rate, the advantage lies between the monoplane and the biplane, the other machines not yet having reached a sufficiently high standard to be able to compete with them.

The monoplane and the biplane have both their own special uses. The monoplane is obviously the lighter machine, and its head resistance is much less, hence it follows logically that its speed will be greater than that of a biplane. But the biplane is a much more stable machine than the monoplane; it will therefore probably be safer and will certainly be able to carry a greater weight.

In the making of aëroplanes wood is usually used for the framework. Specially selected wood is taken, usually from the spruce, hickory, ash, or birch, since wood combines in itself the strength and tenacity of metal without its weight. The fabric with which this frame is covered is more difficult to obtain, since it must contain in itself all the qualities of strength, lightness, smoothness, etc., without any tendencies to shrink, or rot, or burn.

The biplane carries a load of from two and one-half to three and one-half pounds per square foot of surface; the monoplane from three and one-half to six pounds per square foot. The load per horse power in each case is from thirty to forty pounds. In speed the biplane ranges from thirty-five to forty-five miles per hour, as against forty to sixty miles per hour attained by the monoplane.

PRACTICAL USES.--From the very first days the value of the aëroplanes, from a military point of view, has been realized, not as a weapon of offense so much as of intelligence. It would, in fact, be difficult to imagine a better means of scouting and reconnoitering than is afforded by the flying-machine. Its gradually increasing radius of action renders it available for strategical no less than for tactical reconnaissance; its easy mode of progress and absence of vibration allow the most accurate observations to be made and sketch-maps to be drawn. For dispatch-carrying over difficult country its usefulness is also considerable. Its employment for purposes of offense is much more hazardous. On the other hand, it is practically immune from artillery or rifle fire from the land, especially when flying at a fair altitude.

As a commercial vehicle, and for transport, the aëroplane, owing to its relatively low carrying power, is restricted in its usefulness. With increasing reliability, however, it may well assume a portion of the functions of the motor car.

THE MODERN AIRSHIP

The development of the balloon began in 1783, and was the work of two brothers, Joseph and Etienne Montgolfier, who were the sons of a paper manufacturer of Annonay, France.

The latest and most successful experimenter is Count Zeppelin, a German inventor, whose name has been given to the huge dirigible airships known as Zeppelins. Between these there has been a long list of inventors and experimenters who met with varying degrees of success; but the Zeppelins stand paramount.

From the year 1897 the development of the airship was the special work of the Count Zeppelin. In 1900 he made his first flight with a dirigible balloon which carried five men. It was made of aluminum, supported by gas bags and driven by two motors, each about sixteen horse power. His first experiment met with some success, but the first Zeppelin airship was succeeded by another in 1905 with greater motor power; this was wrecked and was succeeded by a third, which met with great success. This airship carried eleven passengers and attained a speed of about thirty-six miles an hour. The fourth Zeppelin airship succeeded in traveling about two hundred and fifty miles in eleven hours, but was wrecked by a storm in 1908, the wreckage catching fire and completely destroying the ship.

Zeppelin VII. had a total length of no less than four hundred and eighty-five feet, a diameter of forty-six feet, and a volume of 690,000 cubic feet. The vessel was fitted with three engines totaling some four hundred and twenty horse power and capable of driving the vessel at thirty-five miles an hour. On one occasion she carried thirty-two people and made a journey of three hundred miles in nine hours.

In the meantime many other experiments had been carried out, notably by Santos Dumont, who circled the Eiffel Tower in the face of a fresh wind.

Dirigibles are divided into three types--(a) rigid, in which there is a framework or skeleton, over which a skin is stretched and within which a number of balloons are placed; (b) semi-rigid, in which the lower part only of the balloon is distended on a flat framework; and (c) non-rigid, when a gas-bag of elongated form has a long girder suspended below it. The propellers are most usually mounted in pairs on each side of the car, but Zeppelin attached them to the balloon itself. To prevent pitching, an “empennage” of flat surfaces is usually arranged near the after-end.

SOME FACTS ABOUT ZEPPELINS.--In shape an ordinary Zeppelin airship is a long cylinder with semisphere-like ends and a keel running the whole length of the bottom thereof. In appearance from a distance the cylinder and pointed ends appear circular in shape, i.e. in cross-section, but in reality this is not so, both being sixteen sided. About one-third the distance from either end of the keel are small boat-like structures suspended from the hull, so close to it that at these places there is a gap in the hull to make room for them. They are rigidly connected with the metallic hull of the airship and help to support it either when the vessel rests on the ground or is towed or driven along the water.

Within these structures are the crew and engines, while above, but outward on each side of the rigid hull and connected with it by means of outriggers, are two pairs of aërial propellers. These are placed at an equal distance out on either side and in the same horizontal plane, so that their united propulsive action shall act centrally along the line of head resistance. The crew can walk through the keel (originally V-shaped) from end to end, or from one boat to the other, the passage being illuminated by means of suitable windows. An observer can also climb through the hull to take observation from the top. Telephones, electric bells, and speaking-tubes are all employed to transmit orders.

CONSTRUCTION OF THE FRAME.--The frame of the rigid hull is built of sixteen longitudinals or girders of trellised or latticed metal; it runs the whole length of the airship and is riveted at regular intervals to cross-sections of latticed girders. Each of these cross-sections is in the form of a sixteen-sided figure or wheel, with latticed rims strengthened by radial rods running from a center flange or boss to the outer rims. The main hull is thus divided into a number of compartments, each separated from one another by means of these latticed radial discs or wheel-like structures and otherwise enclosed by the sixteen latticed girder longitudinals or beams. Each of these compartments contains a gas-bag or balloonette filled with hydrogen; the balloonette fairly fills the compartment, and each bag exerts its proportionate lift. A netting of ramie cords is stretched from wheel to wheel diagonally, between the beams at their inner corners, while the outward corners of the beams are joined by strong wires arranged diagonally for the purpose of imparting rigidity.

The whole frame is covered externally with a strong fabric, which forms the outer skin or wall of the hull. Air-spaces naturally exist between this covering, the inflated balloonettes, and the wheel-like divisions. The entire airship owes its buoyancy to the balloonettes filled with hydrogen, while the outer framework and covering act as a protection against the sun, foul weather, and external shocks.

WAR ZEPPELINS.--Monstrous as the above ships are, they are quite dwarfed by the recent type of military Zeppelins. The latter carry motors aggregating no less than nine hundred horse power. The length varies from five hundred to eight hundred feet, and the diameter is proportional. The gas capacity exceeds a million cubic feet.

AËROPLANE VERSUS AIRSHIP.---On the airship’s side the following strong points are claimed: (1) Greater manœuvering power than the aëroplane, more especially with respect to rapidity of ascent; (2) greater offensive power, i.e. ability to carry heavier guns owing to its far greater lifting capacity; (3) ability to stand still or hover in the air over one spot (for bomb-dropping), or remain stationary in the air, end on to the enemy, for the purpose of obtaining a steady gun platform; (4) greater flying durability, i.e. ability to remain longer in the air at a stretch; (5) ability to fly at night.

MANNING THE AIRSHIP.--The crew of a military airship includes the following: the pilot, the engineer, the steersman, the wireless operator, and last but by no means least the observer. The total number of the crew varies with the size of the airship, and the particular mission in view. The pilot is the captain of the airship, and is responsible for (1) the route, (2) the altitude or elevation at which the airship travels, and (3) the maintenance of the correct pressure on the envelope. The steersman maintains the course ordered him, by means of a compass or by special instructions which may be given him, and also controls the altitude or elevation as ordered. The engineer naturally looks after the engines and the mechanical part of the apparatus with which the airship is fitted.

THE SUBMARINE

Though the submarine boat has only recently been brought to a high degree of practical efficiency, its history extends back to the seventeenth century, and even beyond. The modern submarine, however, whether of the American, English, or German type, has followed the model of J. P. Holland, an American inventor who submitted designs to the United States government in 1895.

In 1901 the English Admiralty gave orders to the firm of Vickers, Maxim & Sons, of Barrow, to construct five of the Holland type and subsequently several were constructed for the United States government.

To France belongs the credit of making submarine boats a real factor in naval warfare. In 1881 M. Goubet designed a small submarine boat, and in 1885 an improved Goubet, which was sixteen feet five inches in length, the motive power being electricity. Successful experiments led the French Admiralty to have the Gymnote constructed at Toulon in 1888; she was fifty-six feet five inches long, with a displacement of thirty tons, her motive power being electricity stored in accumulators, which gave her a radius of thirty-two miles at eight knots. Her trials decided the French authorities to have more vessels built, and by 1901 there were some eleven completed.

In America, the Hollands have been similarly improved, but other types are also in use. The Lake type, named after the inventor, Simon Lake, contains an air-lock through which divers may emerge. These vessels have been adopted by Russia.

Germany started with Hollands, which they have developed along their own lines. The submarine boat is found in all navies now, and has proved an enormously efficient craft; displacements of one thousand tons are not unusual and speeds as well as radius of action have shown great improvement. The Diesel engine has been largely responsible for this. In manœuvers the craft have come up to expectation completely, the experience in actual war has shown them to be among the most formidable of war craft.

There are two distinct types of submarine vessel--the submarine proper, and the submersible. The submarine sinks through the exhaustion of all its buoyancy, and she sinks at once; the submersibles are forced under.

The latter, though equipped to travel on the surface of the water, are specially equipped for sinking quickly out of sight as the occasion arises. The most improved types, such as the recent German U-boats, have lofty armor plated conning towers, torpedo tubes, mounted guns, periscopes, and wireless equipments.

While in the present European war the submarines have shown themselves to be formidable weapons in skillful hands, they are not so formidable as to ring the death-knell of the large battleship, still less perhaps of the swift battle cruiser. Victory has usually rested with the more powerful ship and the heavier guns.

The present-day submarine suffers from two serious drawbacks: (1) inability to see under the water; (2) inefficient speed--the latter being much slower compared with the speed of fast surface boats. The chief chance of a submarine attacking an enemy with success is to come upon him unawares.

The periscopes and other optical tubes with which submarines are fitted, suffer also from many disabilities; and the fact that many collisions have occurred while using them, shows that they are not yet perfect. Obviously one showing not only what is forward of the submarine but what is on the surface of the water on every side is best. One of the drawbacks from which they suffer is the encrustation of salt on their reflecting surfaces; and small though the exposed surface of the periscope may be, there is always the chance of a vigilant enemy detecting it.

THE SUBMARINE IN PEACE.--It is pleasant to record that this invention, like many others of its kind, has not been devoted solely to war, but that peace also can claim its services. The recent remarkable trans-Atlantic voyages of the German submarine Deutschland to American ports is an illustration of their importance to commercial transportation under critical conditions. Since, too, the submarine can sink or dive down to moderate depths, it is obvious it can be used for purposes of underwater salvage, construction, and exploration.

As an aid in the construction of breakwaters, the blowing-up of submerged wrecks in comparatively speaking shallow waters, in searching for sunken treasures, and as an aid to marine explorations in suitable waters, the peace or working submarine is likely to be of untold value.

ELECTRICITY AND MAGNETISM

WHAT IS ELECTRICITY? -- MEANS OF EXCITING ELECTRICITY -- ELECTRIFIED AND NON-ELECTRIFIED BODIES -- CONDUCTORS AND NON-CONDUCTORS OF ELECTRICITY -- ELECTRICAL MACHINES -- POSITIVE AND NEGATIVE ELECTRICITY -- VELOCITY OF ELECTRICITY -- PRINCIPAL AGENTS IN NATURE EXCITING ELECTRICITY -- LIGHTNING -- THREE FORMS OF LIGHTNING -- SHEET AND HEAT LIGHTNING -- DURATION OF A FLASH OF LIGHTNING -- PLACES DANGEROUS IN A THUNDER STORM -- HOW A TREE INFLUENCES LIGHTNING -- LIGHTNING CONDUCTORS -- THEIR PROPER PRINCIPLE OF CONSTRUCTION -- FRANKLIN’S EXPERIMENT WITH A KITE -- IDENTITY OF LIGHTNING AND ELECTRICITY -- UTILITY OF LIGHTNING-RODS -- WHAT IS THUNDER? -- WHAT OCCASIONS THE ROLLING OF THUNDER? -- AURORA-BOREALIS -- EXTENT OF THE AURORA -- HEIGHT OF THE AURORA -- APPEARANCE -- AURORA-BOREALIS OCCURS IN THE DAY-TIME -- WHAT IS GALVANISM? -- HOW GALVANIC ELECTRICITY WAS DISCOVERED -- CONSTRUCTION OF A GALVANIC BATTERY -- ORIGIN OF THE TERM “GALVANISM” -- POLES OF A BATTERY -- MEANS BY WHICH GALVANIC-ELECTRICITY IN QUANTITY CAN BE DEVELOPED -- DIFFERENT FORMS OF GALVANIC BATTERIES -- LIGHT AND HEAT PRODUCED BY GALVANISM -- PRINCIPLES AND PROCESSES OF ELECTRO-METALLURGY -- MAGNETISM -- NATURAL MAGNETS -- WHERE FOUND -- BODIES CAPABLE OF BEING MAGNETIZED -- INDUCTION -- MAGNETIC NEEDLE -- THE MAGNETIC COMPASS -- DISCOVERY AND FIRST USE OF THE COMPASS -- ELECTRO-MAGNETISM -- WHEN AND HOW DISCOVERED -- HOW IRON BARS BECOME MAGNETIC -- HORSE-SHOE MAGNETS -- EXCITATION OF MAGNETISM -- MORSE’S MAGNETIC TELEGRAPH -- TELEGRAPH, MAGNETIC, PRINCIPLES OF -- INTELLIGENCE, HOW CONVEYED BY -- ELECTRIC DYNAMO AND MOTORS -- WIRELESS TELEGRAPHY -- WIRELESS TELEPHONE -- X-RAYS

ELECTRICITY

How may electricity be called into activity?

By mechanical power, by chemical action, by heat, and by magnetic influence.

What is the most ordinary way of exciting electricity?

By friction.

Do we know any reason why the means above enumerated should develop electricity from its latent condition?

We are entirely ignorant upon this subject.

When you rub a piece of paper with India-rubber, why does it adhere to the table?

Because the friction of the India-rubber against the surface of the paper develops electricity, to which this adhesiveness is mainly to be attributed.

Does electricity present any appearance by which it can be known?

No; electricity, like heat, is in itself invisible, though often accompanied by both light and heat.

When a substance, by friction or by any other means, acquires the property of attracting other bodies, in what state is it said to be?

It is said to be electrified, or electrically excited; and its motion towards other bodies, or of other bodies towards it, is ascribed to a force called electric attraction.

Does an electrified body exercise any other influence than an attractive one?

It does; for it will be found that light substances, after touching the electrified body, will recede from it just as actively as they approached it before contact. This is termed electric repulsion.

Thus, if we take a dry glass rod, rub it well with silk, and present it to a light pith ball, or feather, suspended from a support by a silk thread, the ball or feather will be attracted towards the glass. After it has adhered to it a moment, it will fly off, or be repelled. The same will happen if sealing-wax be rubbed with dry flannel, and a like experiment made; but with this remarkable difference, that when the glass repels the ball, the sealing-wax attracts it, and when the wax repels, the glass will attract. These phenomena are examples of electrical attraction and repulsion.

What is a non-electrified body?

One that holds its own natural quantity of electricity undisturbed.

What happens when an electrified body touches one that is non-electrified?

The electricity contained in the former is transferred in part to the latter.

Thus, on touching the end of a suspended silk-thread with a piece of excited wax, the silk will be excited, as will be shown by its moving towards a book, piece of metal, or any other object placed near it.

Do all bodies conduct or allow electricity to pass through them equally well?

Although there is no substance that can entirely prevent the passage of electricity, nor any that does not oppose some resistance to its passage, yet it moves with a much greater facility through a certain class of substances than through others. Those substances which facilitate its passage are called conductors; those that retard or almost prevent it, are called non-conductors.

What substances are good conductors of electricity?

The metals, charcoal, the earth, water, and most fluids, except oils, the human body, etc., are good conductors.

What substances obstruct the passage of electricity, or are “non-conductors”?

Glass, resin, oil, silk, sulphur, dry air, etc., etc., are non-conductors.

What is an electrical machine?

An electrical machine is an arrangement by which quantities of electricity can be collected and discharged.

One type of the electrical machine most usually employed consists of a large circular plate of glass, mounted upon a metallic axis, and supported upon pillars fixed to a secure base, so that the plate can, by means of a handle, be turned with ease. Upon the supports of the glass, and fixed so as to press easily but uniformly on the plate, are four rubbers; and flaps of silk, oiled on one side, are attached to these, and secured to fixed supports by several silk cords. When the machine is put in motion, these flaps of silk are drawn tightly against the glass, and thus the friction is increased, and electricity excited.

Do we know what electricity is?

No; a complete and final answer to this question is no more possible than the answer to the question--what is life? The theory of electricity, however, opens up possibilities of the most fascinating nature; it gives us a wonderfully clear conception of which might be called the inner mechanism of electricity; and it even introduces us to the very atoms of electricity.

Give a short outline of the theory of electricity.

EARLY THEORIES.--Early writers on the nature of electricity supposed it to be either a fluid of peculiar properties or else two fluids whose properties were complementary to each other or of opposite kinds; Franklin held the one fluid theory. Later physicists arrived at the conclusion that whatever electricity might be, it was not a material substance. As an alternative it was suggested that electricity was a form of energy, but this proved untenable.

ELECTRON THEORY.--This, with certain reservations, is held by the scientific world of today. All matter is believed to be constituted of minute particles called “atoms,” whose diameter has been estimated at about one millionth of a millimeter. Up to a few years ago the atom was believed to be quite indivisible, but it has been proved beyond doubt that this is not the case. An atom may be said to consist of two parts, one much larger than the other. The smaller part is negatively electrified, and is the same in all atoms; while the larger part is positively electrified, and varies according to the nature of the atom. The small negatively electrified portion of the atom consists of particles called “electrons,” and these electrons are believed to be indivisible units or atoms of negative electricity.

The electrons in an atom are not fixed, but move with great velocity, in definite orbits. They repel one another, and are constantly endeavoring to fly away from the atom, but they are held in by the attraction of the positive core. So long as nothing occurs to upset the constitution of the atom, a state of equilibrium is maintained and the atom is electrically neutral; but immediately the atom is broken up by the action of an external force of some kind, one or more electrons break their bonds and fly away to join some other atom. An atom which has lost some of its electrons is no longer neutral, but is electro-positive; and similarly, an atom which has gained additional electrons is electro-negative.

THE ELECTRIC CURRENT.--A current of electricity is believed to be nothing more or less than a stream of electrons, set in motion by the application of an electro-motive force. Some substances are good conductors of electricity, while others are bad conductors or non-conductors. In order to produce an electric current, that is a current of electrons, it is evidently necessary that the electrons should be free to move. In good conductors, which are mostly metals, it is believed that the electrons are able to move from atom to atom without much hindrance, while in a non-conductor their movements are hampered to such an extent that interatomic exchange of electrons is almost impossible.

Does electricity seem to exist in two different states or conditions?

It does; and to designate these two conditions, the terms positive and negative have been employed. Thus a body which has an overplus of electricity is called positive, and one that has less than its natural quantity is called negative.

Do light, heat, and electricity appear to have some properties in common?

They do; each may be made, under certain circumstances, to produce or excite the other. All are so light, subtle, and diffusive, that it has been found impossible to recognize in them the ordinary characteristics of matter. Some suppose that light, heat, and electricity are all modifications of some common principle.

Why does the fur of a cat sparkle and crackle when rubbed with the hand in cold weather?

Because the friction between the hand and fur produces an excitation of positive electricity in the hand and negative in the fur, and an interchange of the two causes a spark, with a slight noise.

Why does this experiment work best in very cold weather?

Because the air is then very dry, and does not convey away the electricity as fast as it is excited; if the air, on the contrary, were moist, the electricity would be conducted off nearly as fast as it was excited by friction, and its effects would not therefore be so manifest.

With what velocity is electricity transmitted through good conductors?

With a velocity so great that the most rapid motion produced by art appears to be actual rest when compared to it. Some authorities have estimated that electricity will pass through copper wire at the rate of two hundred and eighty-eight thousand miles in a second of time--a velocity greater than that of light.

What agents are undoubtedly the most active in producing and exciting electricity in the operations of nature?

The light and the sun’s rays.

Do some animals have the power of exciting electricity within themselves?

There are certain animals which are gifted with the extraordinary power of producing electrical phenomena by an effort of muscular or nervous energy. Among these the electrical eel and the torpedo are most remarkable.

How powerful a charge of electricity can the electrical eel send forth when in full vigor?

Sufficient to knock down a man or stun a horse.

Is the electricity generated by these animals the same as that occasioned by the ordinary electrical machine?

It is the same, and produces the same effects.

Do vital action and muscular movements in man and animals give rise to electricity?

They do; and it can be shown by direct experiment that a person cannot even contract the muscles of the arm without exciting an electrical action.

Does change of form or state in bodies generally produce electrical excitation?

Change of form or state is one of the most powerful methods of exciting electricity.

Water, in passing into steam by artificial heat, or in evaporating by the action of the sun or wind, generates large quantities of electricity. The crystallization of solids from liquids, all changes of temperature, the growth and decay of vegetables, are also instrumental in producing electrical phenomena.

What is lightning?

Lightning is accumulated electricity, generally discharged from the clouds to the earth, but sometimes from the earth to the clouds.

What causes the discharge of an electric cloud?

When a cloud overcharged with electric fluid approaches another which is undercharged, the fluid rushes from the former into the latter, till both contain the same quantity.

Is there any other cause of lightning besides the one just mentioned?

Yes; sometimes mountains, trees, and steeples will discharge the lightning from a cloud floating near, and sometimes the electricity passes from the earth into the clouds.

How high are the lightning clouds from the earth?

Sometimes they are elevated four or five miles high, and sometimes actually touch the earth with one of their edges; but they are rarely discharged in a thunder storm when they are more than seven hundred yards above the surface of the earth.

What is a thunder storm?

The disturbance caused in the air when successive discharges of accumulated electricity take place.

Into how many kinds has lightning been divided?

Three.

What are they?

The zig-zag lightning, sheet lightning, and ball lightning.

Why is lightning sometimes forked?

Because the lightning cloud is at a great distance; and the resistance of the air is so great that the electrical current is diverted into a zig-zag course.

How does the resistance of the air make the lightning zig-zag?

As the lightning condenses the air in the immediate advance of its path, it flies from side to side, in order to pass where there is the least resistance.

Why is the flash sometimes quite straight?

Because the lightning cloud is near the earth, and as the flash meets with very little resistance, it is not diverted; in other words, the flash is straight.

What is sheet lightning?

Either the reflection of distant flashes not distinctly visible or beneath the horizon, or else several flashes intermingled.

What other form does lightning occasionally assume?

Sometimes the flash is globular, which is the most dangerous form of lightning.

Does a discharge produce a flash when it passes through good conductors?

It does not, but passes quietly and invisibly.

What is heat lightning?

Sometimes it is the reflection in the atmosphere of the lightnings of storms very remote, the storms themselves being so far distant that their thunders cannot be heard. This phenomenon is also occasioned by the play of silent flashes of electricity between the earth and the clouds, the amount of electricity developed not being sufficient to produce any other effects than the mere flash of light.

Why is lightning more common in summer and in autumn than in spring and winter?

Because the heat of summer and autumn produces great evaporation, and the conversion of water into vapor always develops electricity.

How long is the duration of a flash of lightning?

Arago has demonstrated that it does not exceed the millionth part of a second.

With what velocity is lightning, or the electric fluid which gives rise to its appearance, supposed to move?

Not less than two hundred and fifty thousand miles per second.

By whom was the identity of lightning and electricity first established?

By Dr. Franklin, at Philadelphia, in 1752.

The manner in which this fact was demonstrated, was as follows:

Having made a kite of a large silk handkerchief stretched upon a frame, and placed upon it a pointed iron wire connected with the string, he raised it upon the approach of a thunder storm. A key was attached to the lower end of the hempen string holding the kite, and to this one end of a silk ribbon was tied, the other end being fastened to a post. The kite was now insulated, and the experimenter for a considerable time awaited the result with great solicitude. Finally, indications of electricity began to appear on the string; and on Franklin presenting his knuckles to the key, he raised an electric spark. The rain beginning to descend, wet the string, increased its conducting power, and vivid sparks in great abundance flashed from the key.

Why was the kite insulated when Franklin fastened the key to the post with a silk ribbon?

Because the silk was a non-conductor, and would not allow the electricity received upon the kite to pass off by means of the string to the ground.

Was this experiment one of great danger and risk?

It was; because the whole amount of electricity contained in the thunder cloud was liable to pass from it, by means of the string, to the earth, notwithstanding the use of the silk insulator.

Have we any proof of the utility of lightning rods?

The experience of a hundred years has shown that when all the necessary rules have been observed, the protection is perfect, as far as human effort can avail.

Is a building more or less liable to be struck when furnished with a good lightning conductor?

Lightning conductors do not, as many suppose, attract the lightning toward the building on which they are situated; they simply direct its course, and facilitate the passage of the fluid in the most direct way to the earth, only when a discharge must inevitably occur. There is no attraction, but the lightning takes the road which offers the least resistance.

What is thunder?

It is a certain noise proceeding apparently from the clouds, which usually follows, after a greater or less interval, the appearance of a flash of lightning.

How is it supposed to be occasioned?

The usual explanation offered is a sudden displacement of the air produced by the electrical discharges in which the lightning is evolved.

Others have supposed that the passage of the electric current creates a vacuum, and that the air rushing in to fill it produces the sound. Any explanation that has yet been offered is not altogether satisfactory.

What occasions the rolling of the thunder?

It has been ascribed to the effect of echo; but the true cause probably is, that the sound is developed by the lightning in passing through the air, and consequently separate sounds are produced at every point through which the lightning passes.

Why is thunder sometimes one vast crash?

Because the lightning cloud is near the earth; and as all the vibrations of the air (on which sound depends) reach the ear at the same moment, they seem like one vast sound.

Why is the thunder generally heard several moments after the flash?

Because it has a long distance to travel. Lightning travels nearly a million times faster than thunder; if, therefore, the thunder has a great distance to come, it will not reach the earth till a considerable time after the flash.

Can we not tell the distance of a thunder cloud by observing the interval which elapses between the flash and the peal?

Yes; the flash is instantaneous, but the thunder will take a whole second of time to travel three hundred and eighty yards; hence, if the flash be five seconds before thunder, the cloud is nineteen hundred yards off.

i.e. 380 × 5 = 1900 yards.

What is the aurora borealis or northern lights?

Luminous appearances seen in the sky at night-time. Sometimes streaks of blue, purple, green, red, etc., and sometimes flashes of light, are seen.

What is the cause of the aurora borealis or northern lights?

Electricity in the higher regions of the atmosphere is undoubtedly an active agent in producing this phenomenon.

Is the aurora ever seen in other parts of the heavens than towards the north?

In the northern hemisphere it always appears in the north, but in the southern hemisphere it appears in the south: it seems to originate at or near the poles of the earth, and is consequently seen in its greatest perfection within the arctic and antarctic circles.

What is known concerning the extent of the aurora?

It is not local, but it is seen simultaneously at places widely remote from each other, as in Europe and America.

What calculations have been made respecting the height of the aurora?

The height of the appearances varies from one to two hundred miles; they sometimes appear within the region of the clouds, and very near to the earth.

Do the auroras appear at any particular seasons and times?

They appear more frequently in the winter than in the summer, and are only seen at night.

Do they also occur in the day-time?

The aurora is known to affect the magnetic needle and the telegraph; and as the effects upon these instruments are noticed by day as well as by night, there can be no doubt of the occurrence of the aurora at all hours. The intense light of the sun renders the auroral light invisible during the day.

Of what utility are the auroral appearances in the polar regions?

During the long polar night, when the sun is absent, the aurora appears with a magnificence unknown in other regions, and affords light sufficient for many of the ordinary outdoor employments.

MAGNETISM

Is there any connection between magnetism and electricity?

There is every reason to believe that magnetism and electricity are but modifications of one force.

What is a loadstone or a natural magnet?

It is an ore of iron, known as the “protoxide of iron,” or “magnetic oxide of iron,” which is capable of attracting other pieces of iron to itself; and if suspended freely by a thread, and left to take its own position, it will arrange itself so that its extremities will point towards the north and south poles of the earth.

Are natural magnets rare?

They are not; they are found in many places in the United States. In Arkansas, especially, an ore of iron possessing remarkably strong attractive powers is very abundant.

The magnetic ore is usually of a dark gray hue, and possesses but little metallic luster. If a piece of this ore be dipped in iron filings, or a number of small needles, they will generally be found collected and clinging together in great quantities at two opposite extremities, whilst the middle portion is nearly destitute. The magnetic property, whatever it may be, seems therefore to be collected and act with the greatest energy at two opposite extremes; these have been termed poles.

What is the origin of the terms “magnet” and “magnetism”?

The loadstone or natural magnet was first found at Magnesia, in Lydia, Asia, whence were derived the names.

Can a natural magnet communicate its attractive properties to other bodies by contact?

It can, and that too without any apparent loss of attractive strength.

What bodies are capable of being magnetized by contact with natural magnets?

Iron and steel are the substances most susceptible of this influence, but brass, nickel, and cobalt can also become magnets.

Does the magnetism imparted to a piece of soft iron, or steel, by contact with a natural magnet, remain permanent in their substances?

In the steel it does, but the soft iron loses its power as soon as it is removed from the magnet.

Is it necessary that absolute contact should take place between a magnet and a piece of soft iron to render the latter a magnet?

No, every piece of soft iron brought near a magnet becomes by induction itself a magnet.

What do you mean by induction?

It is the production of like effects in contiguous bodies. In electricity or magnetism, it is the influence exerted by an electrified or magnetized body through a non-conducting medium without any apparent communication of a current.

What is meant by the directive power of the magnet?

It is that power which will cause a magnet, when suspended freely, to constantly turn the same part towards the north pole and the opposite part towards the south pole of the earth.

What are the poles of a magnet?

They are the ends of the magnet, and are denominated north and south, according as they point to the north or south poles of the earth.

What are the poles of the earth?

The extremities of the earth’s axis, or the points on the surface of the globe through which the axis passes.

What is a magnetic needle?

Simply a bar of steel which is a magnet, suspended in such a way that it can freely turn to the north or south.

What is a mariner’s compass?

It is a delicate steel bar or needle balanced upon a pivot placed beneath its center of gravity in such a way that it can turn horizontally without obstruction. This needle is usually inclosed in a box, upon the bottom of which is a card, with the various points--north, south, east, west, etc., etc., marked upon it.

Such a needle, if the box containing it be placed on a level surface, will generally be observed to vibrate more or less, till it settles in such a direction that one of its extremities or poles will point towards the north, and the other consequently towards the south. If the position of the box be altered or reversed, the needle will always turn and vibrate again, till its poles have attained the same direction as before.

Does the compass needle always point exactly north and south?

It does not; its natural direction is towards the north and south poles, but it seldom points due north or south.

Who first discovered the fact that a magnet would invariably point to the north and the south, and made use of this knowledge in constructing a compass?

It is claimed to have been discovered by the Chinese: it was known in Europe, and used in the Mediterranean, in the thirteenth century.

How were the compasses of that time constructed?

They were merely pieces of loadstone fixed to a cork, which floated on the surface of water.

Is the earth itself supposed to be a magnet?

It is undoubtedly a great magnet.

Is iron under certain circumstances rendered magnetic by the inductive action of the earth’s magnetism?

Most iron bars and rails, as the vertical bars of windows, that have stood for a considerable time in a perpendicular position, will be found to be magnetic.

If we suspend a bar of soft iron sufficiently long in the air, will it assume magnetic properties?

It will gradually become magnetic; and although when it is first suspended it points indifferently in any direction, it will at last point north and south.

How may a bar of iron, such as a kitchen poker, be made immediately magnetic, without resorting to the use of other magnets?

If the bar devoid of magnetism is placed with one end on the ground, slightly inclined towards the north, and then struck one smart blow with a hammer upon the upper end, it will immediately acquire polarity, and exhibit the attractive and repellant properties of a magnet.

What is a horseshoe magnet?

It is a magnetic bar bent into the form of a horseshoe.

When a piece of iron not magnetic is brought in contact with a common magnet, it will be attracted by either pole; but the most powerful attraction takes place when both poles can be applied to the surface of the piece of iron at once. The magnetic bars are for this purpose bent into the shape of the letter U, and are termed horseshoe magnets. Several of these are frequently joined together with their similar poles in contact; they then constitute a magnetic battery, and are very powerful, either for lifting weights, or charging other magnets.

If we break a magnet across the middle, what happens?

Each fragment becomes converted into a perfect magnet; the part which originally had a north pole acquires a south pole at the fractured end, and the part which originally had a south pole, gets a north pole.

If we divide a magnet to the extreme degree of mechanical fineness possible, will the pieces possess magnetic powers?

Each fragment, however small, will be a perfect magnet.

GALVANISM

What is galvanism?

It is the production of electrical disturbance by chemical action.

What is the most simple manner of illustrating the production of this electricity?

If we place a piece of silver on the tongue, and a piece of zinc underneath it, no effect will be produced as long as the two metals are kept asunder; but when their ends are brought together, a distinct thrill will pass through the tongue, a metallic taste will diffuse itself, and, if the eyes are closed, a sensation of light will be evident at the same moment.

To what is this result owing?

To a chemical action developed the moment the two metals touched each other.

The saliva of the tongue oxidizes a portion of the zinc, which excites electricity, for no chemical action ever takes place without producing electricity. Upon bringing the ends of the two metals together, a slight current passes from one to the other.

By whom was the production of galvanic electricity first noticed?

By Galvani, professor of anatomy at Bologna, Italy, in 1790.

Having occasion to dissect several frogs, he hung up their hind legs on some copper hooks, until he might find it necessary to use them for illustration. In this manner he happened to suspend a number of the copper hooks on an iron balcony, when, to his great astonishment, the limbs were thrown into violent convulsions.

On investigating the phenomena what did Galvani discover?

He found that whenever the nerves of a frog’s leg were touched by one metal and the muscles by another, convulsions took place on bringing the two different metals in contact.

What is the simplest way of exciting a current of galvanic electricity?

By arranging a series of metal plates in a pile, placing them in pairs, with a wet cloth between them, it being necessary that one of each pair should be more easily oxidized than the other. The simple contact of these plates will produce a feeble and continued galvanic current.

What is such an arrangement of plates for producing electrical currents called?

A galvanic or voltaic battery.

Why are the terms “galvanic” and “voltaic” applied?

They originated in honor of Galvani and Volta, the Italian philosophers who first developed these phenomena of chemical electricity, and the means of producing them.

Are there many metals or other substances which, when brought together, are capable of producing galvanic action?

The number is quite large; among them we may enumerate the following: zinc, lead, tin, antimony, iron, brass, copper, silver, gold, platinum, black lead or graphite, and charcoal.

Will any two of these brought together produce a galvanic current?

They will; but they possess the power in different degrees; and the more remote they stand from each other in the order above given, the more decidedly will the chemical electricity be developed.

Thus zinc and lead will produce a voltaic battery, but it will be much less active than zinc and iron, or the same metal and copper, and this last less active than zinc and platinum, or zinc and charcoal.

Does galvanic or voltaic electricity appear to consist of two kinds, positive and negative, as in ordinary electricity?

It does; positive electricity always flows from the metal which is acted upon most powerfully, and negative electricity from the other.

What do we mean when we speak of a galvanic circuit?

The connection of the two metals in the battery, so that the positive and negative electricities can meet, and flow in opposite directions.

At what point in the circuit will the manifestations of electricity be most apparent?

At the point where the two currents meet.

What is meant by the poles of the battery?

The two metals forming the elements of the battery are generally connected by copper wires; the ends of these wires, or the terminal points of any other connecting medium used, are called the poles of the battery.

Thus, when zinc and copper poles are used, the end of the wire conveying positive electricity from the zinc would be the positive pole, and the end of the wire conveying negative electricity from the copper plate would be the negative pole. Faraday describes the poles of the battery as the doors by which electricity enters into or passes out of the substance suffering decomposition.

A very simple, and at the same time an active, galvanic circuit may be formed by an arrangement as represented in the accompanying illustration. The current of positive electricity, when the circuit is closed, passes from the zinc, through the liquid, to the copper, and from the copper, along the conductors to the zinc. A current of negative electricity traverses the circuit also, from the copper to the zinc, in a direction precisely reversed.

By what chemical action can the greatest abundance of galvanic electricity be developed?

By the oxidation of metallic zinc by weak sulphuric acid.

The electricity developed by the action of a single pair of plates immersed in acid water is very feeble: how can it be increased?

By increasing the number of the plates and the quantity of the liquid, we increase the intensity of the electricity developed.

ACTION WITHIN A VOLTAIC CELL.--Let us try to see now how an electric current is set up in a simple voltaic cell, consisting of a zinc plate and a copper plate immersed in dilute acid. First we must understand the meaning of the word ion.

If we place a small quantity of salt in a vessel containing water, the salt dissolves, and the water becomes salt, not only at the bottom where the salt was placed, but throughout the whole vessel. This means that the particles of salt must be able to move through the water. Salt is a chemical compound of sodium and chlorine, and its molecules consist of atoms of both these substances. It is supposed that each salt molecule breaks up into two parts, one part being a sodium atom, and the other a chlorine atom, and further, that the sodium atom loses an electron, while the chlorine atom gains one. These atoms have the power of traveling about through the solution, and they are called ions, which means “wanderers.”

An ordinary atom is unable to wander about in this way, but it gains traveling power as soon as it is converted into an ion, by losing electrons if it be an atom of a metal, and by gaining electrons if it be an atom of a non-metal.

Returning to the voltaic cell, we may imagine that the atoms of the zinc which are immersed in the acid are trying to turn themselves into ions, so that they can travel through the solution. In order to do this each atom parts with two electrons, and these electrons try to attach themselves to the next atom. This atom, however, already has two electrons, and so in order to accept the newcomers it must pass on its own two. In this way electrons are passed on from atom to atom of the zinc, then along the connecting wire, and so to the copper plate. The atoms of zinc which have lost their electrons thus become ions, with power of movement. They leave the zinc plate immediately, and so the plate wastes away or dissolves. So we get a constant stream of electrons traveling along the wire connecting the two plates, and this constitutes an electric current.

What are the most ordinary effects produced by the developed electricity of a large galvanic battery?

The production of sparks and brilliant flashes of light, the heating and fusing of metals, the deflagration of gunpowder and other inflammable substances, and the decomposition of water, saline compounds, and metallic oxides.

How may the most splendid artificial light known be produced?

By fixing pieces of pointed charcoal or carbon to the wires connected with opposite poles of a powerful galvanic battery, and bringing them into contact.

What does this produce?

Electric light.

Can intense heat be developed by the action of the galvanic battery as well as intense light?

The greatest artificial heat man has yet succeeded in producing has been through the agency of the galvanic battery.

What refractory substances can be fused by the aid of the galvanic battery?

All the metals, including platinum, can be readily melted; quartz, sulphur, magnesia, slate and lime are liquefied; and the diamond fuses, boils, and becomes converted into coal.

What is electrotyping, or electro-metallurgy?

It is the art or process of depositing, from a metallic solution, through the agency of galvanic electricity, a coating or film of metal upon some other substance.

Upon what principles is it accomplished?

The process is based on the fact, that when a galvanic current is passed through a solution of some metal, as a solution of sulphate of copper (sulphuric acid and copper), decomposition takes place; the metal is separated in a metallic state, and attaches itself to the negative pole, or to any substance that may be attached to the negative pole; while the acid or other substance before in combination with the metal, goes to, and is deposited on the positive pole.

In this way a medal, a wood-engraving, or a plaster cast, if attached to the negative pole, may be covered with a coating of copper; if the solution had been one containing silver or gold, the substance would have been covered with a coating of silver or gold instead of copper.

How can the thickness of the deposits be regulated?

The thickness of the deposit, providing the supply of the metallic solution be kept constant, will depend on the length of time the object is exposed to the influence of the battery.

ELECTRO-MAGNETISM

What is electro-magnetism?

It is the magnetism developed through the agency of electrical or galvanic action.

What were the earliest phenomena observed which indicated a relation between magnetism and electricity?

It was noticed that ships’ compasses have their directive power impaired by lightning, and that sewing needles could be rendered magnetic by electric discharges passed through them.

What discovery, made by Prof. Oersted of Copenhagen, established beyond a doubt the connection of electricity and magnetism?

He ascertained that a magnetic needle placed near a metallic wire connecting the poles of a galvanic battery was compelled to change its direction, and that the new direction it assumed was determined by its position in relation to the wire and to the direction of the current transmitted along the wire.

Thus, if a needle be inclosed in a wire not touching it at any point, and a current of electricity pass through the wire, the needle will be made to move in accordance with the direction of the current.

What other important discovery was made about the same time?

It was found that if a piece of soft iron, not possessing magnetic power sufficient to elevate a grain weight, be placed within a coil of copper wire through which a galvanic current is passing, it will become, through the influence of the current, a powerful magnet; and will, so long as the current flows, sustain weights amounting to many hundreds of pounds.

Is the magnetic power of the bar found to be wholly dependent on the existence of the current?

It is; the moment the current stops, the weights fall away from the bar in obedience to the law of gravity.

How great weights have been lifted by magnets formed in this manner?

An electro-magnet constructed by Prof. Henry was capable of elevating and sustaining about a ton weight.

Upon what principle does the construction of the Morse magnetic telegraph depend?

Upon the principle that a current of electricity circulating about a bar of soft iron is capable of rendering it a magnet.

Why is it necessary, in conveying the telegraph wires, to support them upon glass or earthen cylinders?

These are used for the purpose of insuring the perfect insulation of the wires, since but for this the electricity would pass down a damp pole to the earth, and be lost.

Is there any truth in the idea that many persons have, that some principle passes along the telegraphic wires when intelligence is transmitted?

This supposition is wholly erroneous; the word current, as something flowing, conveys a false idea, but we have no other term to express electrical progression.

How can we gain an idea of what really takes place, and of the nature of the influence transmitted?

The earth and all matter are reservoirs of electricity; if we disturb this electricity at Boston by voltaic influence, its pulsations may be felt in Chicago. Suppose the telegraphic wire were a tube, extending from Boston to Chicago, filled with water. Now, if one drop more is forced into it at Boston, a drop must fall out at Chicago, but no drop was caused to pass from Boston to Chicago. Something similar to this occurs in the transmission of electricity.

What was the earliest important industrial application of electricity?

One of the earliest industrial applications of electricity was to the driving of street cars. The first electric railway was installed by Siemens, of Berlin, in 1882; and the system was quickly taken up and brought to a high state of development by American engineers. It is remarkable that the system of traction early adopted is the one generally used in America and Europe until the present date. It consists essentially of (a) a supply of continuous current at five hundred to five hundred and fifty volts, generated in (b) a central powerhouse, and transmitted to the car by means (c) of overhead conductors, whence by contact with a trolley wheel on a pole on the car it is led down to (d) two series-excited motors, which are placed electrically first in series with one another at starting, and then in parallel with one another when a sufficient speed has been attained.

To what well-known electrical machines did this give impetus?

Electric dynamos and motors. All such machines will convert the energy of mechanical motion into that of electricity in motion, or the reverse. The former conversion is done by dynamos, to which power is given by steam-engines or other such prime-movers, and made to generate in conducting circuits alternate or direct currents of electricity. Motors, on the other hand, receive the energy of electrical currents, either alternate or direct, and this produces motion of certain parts of the structure.

The theory of the action of a dynamo was first discovered by Faraday in 1831; it is intimately associated with that of a motor, for the principle of conservation of energy points out that either machine is reversible--that is to say, a dynamo may be used as a motor or a motor as a dynamo, though perhaps not so efficiently as when each fulfills the special function for which it was designed.

THE CURRENT IN A DYNAMO OR MOTOR.--This brings us to the production of an electric current by the dynamo. In the dynamo we have a coil of wire moving across a magnetic field, alternately passing into this field and out of it. A magnetic field is produced, as we have just seen, by the steady movement of electrons, and we may picture it as being a region of the ether disturbed or strained by the effect of the moving electrons. When the coil of wire passes into the magnetic field, the electrons of its atoms are influenced powerfully and set in motion in one direction, so producing a current in the coil. As the coil passes away from the field, its electrons receive a second impetus, which checks their movement and starts them traveling in the opposite direction, and another current is produced. The coil moves continuously and regularly, passing into and out of the magnetic field without interruption; and so we get a current which reverses its direction at regular intervals, that is, an alternating current.

A .- B -... C -.-. D -.. E . F ..-. G --. H .... I .. J .--- K -.- L .-.. M -- N -. O --- P .--. Q --.- R .-. S ... T - U ..- V ...- W .-- X -..- Y -.-- Z --.. 1 .---- 2 ..--- 3 ...-- 4 ....- 5 ..... 6 -.... 7 --... 8 ---.. 9 ----. 0 -----

THE MORSE TELEGRAPH CODE FOR LETTERS AND FIGURES

What are some of the chief modern applications of electricity?

The field of applied electricity is one of the most extensive in modern science, invention and industry. Electricity in some form is now utilized in connection with lighting, telegraphy, the telephone, heating, motor boats, railways, aëroplanes, in metallurgy and the arts, clocks, bells and alarms, wireless telegraphy and telephony, submarine telegraphy, automobiles, cooking and domestic science, in medicine and in military science.

Give a brief account of wireless telegraphy.

In the case of ordinary telegraphy we always make use of extended metallic wires or conductors from the place from which the message is sent to the neighborhood to which it is desired to send it. In the case of wireless telegraphy no such conductors exist.

Among the most interesting of the many systems of wireless telegraphy now in vogue the modern Marconi, the De Forrest, the Fessenden, and the Poulsen are noteworthy. It is, however, with the name of Marconi that the introduction of wireless telegraphy will always be directly associated.

In 1888 Hertz had demonstrated in a remarkable series of experiments the existence of electro-magnetic waves, and had even shown how these might be produced, detected, and made to exhibit all the chief phenomena of wave-motion. Marconi’s great achievement lay in so controlling and regulating the dispatch and receipt of such waves as to make them record signals on a specially designed apparatus in accordance with the well-known Morse telegraphic system. His method, as first patented in 1896, was briefly as follows:

THE TRANSMITTER, by which the electromagnetic waves were generated and sent off into space in all directions, consisted of a battery connected through a key to the primary of an induction coil whose secondary terminals were joined to two brass balls between which there was a short air-gap. From one of these balls a wire was taken to earth, and from the other an aërial wire was led some distance up in the air. The closing of the primary circuit led to sparks passing across the air-gap, which produced electro-magnetic waves in the ether in exactly the same way as the dropping of a stone into a pool produces a series of concentric ripples.

THE COHERER.--To receive and interpret these waves Marconi employed a “coherer” in circuit with a battery and having connection with an aërial wire on the one side and an earth wire on the other. The coherer consisted of a small glass tube not more than, say, two inches long by one-quarter inch in diameter, into the ends of which were fused two platinum wires leading to small metallic electrodes. These electrodes were brought quite near each other, and in the narrow gap between them was placed powdered metallic silver, antimony, etc. The resistance offered by this powder was so high, on account of small air-gaps between the particles, that no current could pass through.

Electro-magnetic waves, however, possess the peculiar property of breaking down the resistance of this powder whenever they impinge upon it. Hence as soon as a wave reached the coherer, the resistance practically vanished and a current passed round the circuit. It was a mere detail to arrange that this current should actuate a relay connected with a telegraphic instrument which would record the signal, and that a hammer would at the same time tap the coherer so as to agitate the powder and “decohere” it, setting up the resistance again for a fresh signal.

IMPROVEMENTS.--Since this system was devised many most important improvements have taken place. One of the most noticeable of these was Sir Oliver Lodge’s invention of tuning and syntonizing apparatus by which a transmitter and receiver are tuned to the same periodic oscillation, and thus a number of messages might be operated in the same field without interference. Lodge accomplished this to some extent by adding inductance coils and condensers to the circuits. Various other methods have been adopted to secure syntonization; but the resonance effects obtained are not great enough to make selective signaling certain.

THE GENERATOR.--In the modern Marconi system the energy for the transmitter is obtained from a generator working at one hundred and ten volts. The current is led through a key and an improved form of interruptor to the primary of the induction coil, whose secondary terminals communicate with the spark-gap. The spark-gap is in series with a condenser and the primary of a high tension transformer, of which latter one secondary terminal leads to the aërial and the other to the earth wire.

THE DETECTOR.--In the receptor the metallic coherer has been discarded for a magnetic detector. This instrument consists of a small glass tube through which travels an endless band of iron wires, moving round two grooved pulleys. Close to the tube are two permanent magnets, and round it is wound a primary coil consisting of one layer of wire. One end of this coil is led straight to earth; the other passes through a condenser to a tuning inductance coil leading in one direction to earth and in the other to the aërial. Above the primary coil on the glass tube a secondary coil is wound and connects with a telephone receiver. The action is simple. The electro-magnetic waves, reaching the aërial, set up oscillatory currents in the primary which act upon the magnetic field. Currents are thus generated in the secondary, which record the message in the telephone receiver by a series of taps corresponding to the Morse dashes and dots.

The De Forrest system is very largely used in the United States, Japan, and elsewhere, and in its more recent modifications secures a high efficiency by means of a number of ingenious improvements.

Describe the wireless telephone.

As in wireless telegraphy, all modern systems of wireless telephony are based upon the action of electro-magnetic waves. It is impossible here to discuss all the various methods that have been devised, but the leading principles employed may be indicated, with special reference to some of the best-known systems. They may be classified according to the methods in which the waves are produced.

SPARK DISCHARGE SYSTEMS.--These rely for the generation of the Hertzian waves upon a spark discharge across an air-gap. The De Forrest system is perhaps the most popular of this type. In this system the spark discharge is utilized to produce waves of a frequency not less than one hundred thousand per second, the resulting sound being inaudible at the receiving station.

A microphone transmitter is employed with this apparatus. When the operator speaks into the transmitter, the variations of resistance act upon the waves in such a way as to produce a new series of waves of such frequency as to be audible at the receiver.

The receiving apparatus includes the usual antenna, and closed secondary circuit, comprising an inductance and a variable capacity, across the terminals of which an Audion delicate detector is introduced. This instrument depends upon the motions of the ions in a rarefied gas. It is one of the most sensitive detectors yet invented, and offers the great advantage of a practically total absence of time lag in recovery.

SINGING-ARC SYSTEMS.--Duddell’s discovery of the singing arc in 1909 has been quickly followed by its application to radio-telephony and radio-telegraphy, first by Poulsen and subsequently by Fessenden, Stone, De Forrest, and others. Under certain conditions the electric arc can be made to emit a musical note, while at the same time it transforms a portion of the energy of its own direct current into oscillations. These are led into an oscillation circuit containing a condenser and inductance, and associated with an antenna and earth line. The microphone transmitter may be included in a circuit associated with the inductance, in which case the voice acting on the resistance of the transmitter causes variations in the oscillating currents; or it may be associated with some part of the direct-current circuit, in which case it acts by affecting the current passing across the arc.

Any form of receiver may be used with this arc apparatus. The great advantage of this method is that the arc produces continuous oscillations of constant amplitude, and that the wave-length and frequency of the oscillations are subject to better regulation and control.

ADVANTAGES.--The advantages of wireless telephony over wireless telegraphy are many. One is that no skilled operator is required to translate the dot-and-dash signals; for in the latter one hears only long and short buzzes, whereas in the former one hears the actual spoken words. By means of wireless telephony the transmission of intelligence is far more direct and expeditious, and in times of emergency this not unfrequently becomes a very vital question indeed. An important characteristic of wireless telephonic communication is the exceptional clearness of the articulation, owing to the absence of the electrostatic capacity of metallic lines and cables which is always present in wire telephony.

Stronger currents, improved sending and receiving apparatus, and the application of new principles have now greatly extended the speaking range; and only recently distinct communication has been established by wireless telephony between New York and San Francisco. The use of the wireless telephone will be greatly extended, especially in naval, military, and shipping communication.

THE MARVEL OF X-RAYS

Röntgen or X-Rays, the most famous, and up to now by far the most useful, kind of rays associated with high vacuum tubes, were discovered by Professor W. K. Röntgen in 1895. His first observation was that a photographic plate, which was enclosed in an opaque material and which was lying by chance near the apparatus, was affected just as if it had been exposed to ordinary light. This caused him to conclude that the effect must be due to some unknown kind of rays, and the uncertainty as to their character led him to provisionally apply to them the name of X-rays, for x in algebra generally denotes the unknown quantity.

The later sensational part of his discovery was that the property possessed by a highly exhausted bulb of glass, fitted with suitable electrodes, sends out rays or electric discharges capable of passing through many bodies which are quite opaque to ordinary light, and of either affecting a photographic plate or causing a screen coated with certain chemicals to fluoresce or light up under their influence.

How are X-rays produced?

X-rays are thus produced by the discharge of a high-potential current through a special form of vacuum tube, known as a Crookes’ tube. The positive terminal of an induction coil or Wimshurst machine is connected to the anode and the negative to the cathode of the tube. The anticathode is connected to the anode and is also positive. The vacuum of a tube is not perfect, and the current is conveyed through the tube by the infinitesimal quantity of air contained therein.

The “cathodal rays” which pass from the cathode to the anticathode consist of infinitesimal particles traveling at a high rate of speed; when the progress of these minute bodies is arrested, X-rays are produced. The green fluorescence on the sides of the tube opposite the anticathode, though not caused by the X-rays, demonstrate their presence.

WHAT THE X-RAYS ARE.--The X-rays are ethereal vibrations traveling with much the same velocity as light. They travel in a straight line in all directions from the point of origin, and are almost incapable of reflection or refraction.

X-rays are invisible to the eye, but have the property of rendering fluorescent certain substances--for example, calcium tungstate and barium platino-cyanide. When a screen coated with these substances is placed near the X-ray tube in a darkened room, the tungstate or barium surface emits a fairly bright fluorescence. If an object such as the hand or a lead pencil is placed between the screen and the tube, the denser parts (the bones or the graphite) appear as black shadows in a gray background.

X-rays penetrate all substances to a greater or less degree, although heavy metals, such as lead and mercury, are, for photographic or visual purposes, practically opaque to the rays.

The greater part of X-ray examination is conducted by photographic methods, as the image given by the rays on a dry plate or film show far more detail than can be seen by visual examination with the fluorescent screen.

APPARATUS.--The apparatus required consists of a suitable source of electrical energy, such as a battery or dynamo, etc., and a powerful induction or a large electrostatic influence machine, combined of course in either case with an X-ray tube and special X-ray photographic plates. Ordinary photographic plates can be used, but do not give such brilliant results. If we wish to take a radiograph of the hand, we must first of all use a plate slightly larger than the hand, and enclose it in an opaque envelope. Two such are usually employed, one red and the other black. This is placed on the table or stand, film side uppermost, and the hand is placed upon it, and a short distance above the hand is located the X-ray tube. Since what we really take is a shadowgraph picture, to give a good sharp outline, the hand should be placed as flat as possible on the plate, and the tube some six to eight inches from it.

With some of the most powerful apparatus now in use, even the human trunk can be radiographed in a single flash, which is an improvement on the exposure necessary in the early days of its use, when ten, twenty, or even forty minutes’ exposure was no uncommon practice.

THE FLUORESCENT SCREEN.--When the X-rays impinge on certain substances they cause them to light up or “fluoresce” under their action. The number of bodies or chemicals which do so is very large, but for practical purposes only one or two are of any use. The best, and the one always employed, is a chemical known as barium platino-cyanide. The screen-holder consists of a box, preferably of pyramidal form, with a flattened apex or top. Inserted in this apex are two tubes, like opera-glass tubes but without lenses; through these we can look into the box in such a manner as to prevent any outside light from entering. The bottom of the box consists of the screen proper, a piece of cardboard or other suitable substance, one side (the inner) of which is coated with the substance mentioned above, because the light rays given off by the barium platino-cyanide under the action of the X-rays cannot of course penetrate an object opaque to light. The box should be absolutely light-tight except for the eye-tubes.

If such a screen be held in the neighborhood of an X-ray tube, opposite the most brilliantly phosphorescing half of the tube, it will be found to be lighted up under the action of the X-rays. If now we place between the tube and the screen an object such as the hand, putting it in as close proximity to the tube as possible, we obtain a shadowgram on the screen, varying in intensity according to the relative transparency of the different parts of the hand to the X-rays. Since the bones are far less transparent than the flesh, they cast a much denser shadow and are very distinct. On such a screen it is possible to see the beats of the heart, the rising and falling of the diaphragm, etc.

X-RAYS AT WORK.--In medical X-ray work, the patient is placed upon a couch consisting of a wooden frame covered with canvas. A box containing the tube moves on wheels and rails beneath the couch; it is lined with metal to shield the operator from the X-rays. The time of exposure depends upon the strength of current used, the power of the coil, and the condition of the tube. A “hard” tube--that is, a tube with an extremely high vacuum--requires less exposure than a “soft” or low-vacuum tube.

The condition of the tube is ascertained by finding its “equivalent spark gap.” While the coil and tube are working, the terminal points of the induction coil are slowly brought together. If a spark passes between the points while they are six inches or more apart, the vacuum is too high. If no sparking takes place between the terminals till they are within three inches of each other, the tube is low. A good working spark gap distance is four and one-half inches. A soft, or low-vacuum, tube gives better definition than a hard, or high-vacuum, tube, as the rays pass less easily through dense substances and show greater differentiation of tissue. A very high vacuum tube may show but little difference between the bones and flesh, while a soft tube should give the minute structure of the bones.

TIME OF EXPOSURE.--With a current of five amperes at one hundred volts passing through the primary winding of a ten-inch coil, the exposure for a hand or foot would be from three to fifteen seconds. The exposure for the thicker portions of the body would be from twenty seconds to two minutes. If an electrolytic break is used, about half the exposure would be required. Dry plates with extra thick sensitive films are specially prepared for radiography, the development and fixation being the same as in ordinary photography. The image is sometimes barely visible on the surface of the plate during development, but when fixed the negative may give good density and definition owing to the penetration into the film of the X-rays.

KINDS OF X-RAYS.--It is now known that these rays are not all by any means of the same kind or of the same penetrative power. Moreover, these differences can be still augmented by altering what is known as the induction in the circuit, the degree of exhaustion in the tube, and the nature of the emitting surface. The emitting surface is not the glass walls of the tube, as many suppose; and the canary colored light emitted by the tube is not the X-rays, which are themselves invisible. They originate from the anode of the tube owing to the fierce bombardment to which the cathode rays subject it. Where the cathode rays, which travel in straight lines, first strike any material object, from that same object the X-rays originate.

USES OF X-RAYS.--In the early days of radiography the X-rays in medical work were confined almost solely to the detection of fractured or injured bones, and abnormal bone growth. At the present time, however, even a careful examination on the fluorescent screen is sufficient to enable an expert medical radiographist to diagnose with a considerable degree of exactitude the condition of the heart, the lungs, and the stomach. In making such examination a tube must be chosen which has the lowest vacuum, in order to obtain the maximum amount of contrast between fleshy tissue not differing greatly in density.

In some cases even the liver has been outlined and part of the kidneys.

Still more important is the fact that the rays have been applied successfully in the treatment of certain diseases which by other means have been deemed, if not incurable, at any rate extremely difficult to cure. Claims have been made for cancer cures by means of these same rays; whether these have really been complete cures or not is perhaps open to question.

X-RAY DERMATITIS.--A painful and incurable disease, of a cancerous nature, to which radiographers are liable, caused by frequent and prolonged exposure to X-rays. Many of the pioneers of radiography have fallen victims to this complaint, but greater precautions are now taken to protect the operators from the X-rays. There is little danger of contracting this disease in X-ray photography, as the exposures are short and the operator need not stand directly in front of the tube. The chief risk is entailed by visual examination with the fluorescent screen. The disease first makes its appearance in the hands and gradually spreads to the arms and body. The skin at first appears as if it had been burned, hence the term “X-ray burning.”

=LIQUID AIR AND ITS MARVELS OF LOW TEMPERATURE=

BOOK OF THE HUMAN BODY

WHAT THE HUMAN BODY IS

ITS DIVISIONS AND SYSTEMS

GENERAL STRUCTURE OF THE BODY

FRAMEWORK: BONES, MUSCLES AND CELLS

THE DIGESTIVE SYSTEM AND ORGANS

CIRCULATION OF THE BLOOD AND RESPIRATION: HEART, BLOOD VESSELS, LYMPHATICS, LUNGS AND BRONCHII

THE EXCRETORY SYSTEM: INTESTINAL TRACT, KIDNEYS, SWEAT GLANDS, LUNGS

THE NERVOUS SYSTEM: NERVES, BRAIN, SPINAL CORD

ORGANS OF SPECIAL SENSE: EYE, EAR, NOSE, TONGUE, HAND AND SKIN

CHARTS, TABLES AND SPECIAL FEATURES

BOOK OF THE HUMAN BODY

The study of the Human Body involves numerous other branches of science, and, as a whole, is the most complex and intricate of all the sciences. To explain its structure and workings we apply the principles of Biology, Physiology, Chemistry, Physics, Psychology, and Metaphysics.

The individual man, as a whole, is frequently forgotten both in physiology and in medicine, owing to the extraordinary minuteness and exactness with which each part and organ is examined and described. At the outset, then, it should be remembered that the human body is an organic whole, and what makes it one is not the similarity or unity of the machines and processes, for they are unlike and many; but it is the unity of the one governing force, the mind, and especially the unconscious mind, which presides over the body.

Nothing in the body is merely mechanical, although there is much mechanism; all is vital, all is united in one great aim--the health and well-being of the individual.

All organs and systems are held together and formed into one body by means of a framework, partly fixed and partly movable, partly rigid and partly flexible, partly hard and partly soft.

The skeleton part of the framework is made of bone; flexibility is given to certain parts by means of joints, which are simply smoothed and rounded ends of bone covered with gristle to avoid friction, and joined together by fiber and ligament for strength. This forms the rigid and hard parts of the framework.

The flexible and soft part, which everywhere covers organs and muscles, is composed of a layer of fat to preserve the warmth, as fat is a non-conductor, and an outer covering of skin.

This framework is exquisitely adapted to give strong protection to the vital parts so that they cannot readily be injured; and the whole of the organs are so arranged and stowed away that a perfect human body is a beautiful object full of symmetry and graceful curves and lines.

=Divisions of the Body.=--If we divide the body into six parts--four limbs, trunk, and head and neck--we find each part contains about thirty bones (counting the ribs in pairs) there being about two hundred in the entire body.

The height of the body depends mainly on the length of the bones of the lower limbs.

=Everything in Pairs.=--In the body almost everything is paired, right and left, giving it symmetry. There are but five central bones: two in the head, one in the throat, and the breastbone and backbone (or spine); and there are but five single muscles, all the rest--out of many hundreds--being in pairs. In the interior, where economy rather than symmetry is required, it is not so; there being as many single organs as there are double.

=The Body Viewed as a Machine.=--A favorite way of looking at the body as a whole is to regard it as an anatomical machine. In this view the body has an internal skeleton, of which the chief feature is the central axis or backbone.

Considering the skull and backbone as one, the body may be said to be built up of two tubes. The smaller posterior or neural tube includes the cavity of the skull and the vertebral canal. Within this tube is lodged the nervous center, or engine, of the body. The anterior, or body, tube is much larger, consisting of the face above, and the neck and trunk below, and it contains the four nutritive systems of life, so that the whole body in section is like an eight with the lower circle immensely exaggerated. The limbs, of course, are not tubular, and merely form part of the machinery.

Adopting the simile of the human engine and boiler and machinery, we see that the limbs, etc., are the machinery; the posterior tube the engines and force that move them; and the anterior tube the human boiler that generates the force. This boiler, like one in a steam engine, has an upper and lower part. The upper part is where the steam is generated (in lungs) and sent to the engine (the brain) by the heart. The lower part is where the fuel is burned (the stomach) and the ashes and refuse drop through (the intestines). So that the analogy between the two is close and striking.

=Centers of Control.=--There are two distinct seats of government in the human body: the one in the upper brain, or cortex, the other principally in the very center of the human body. That in the upper brain, or cortex, is the human will and the conscious mind. It has absolute control given to it over the animal part of the human life--that is, over the part that consists in the using of force, which includes the nervous and locomotor systems, and the special senses.

Nutritive Systems.--The other government, situated in the lower part of the brain and spinal cord and in the center of the body--in front of the spine and behind the stomach--is of an entirely different order. To put this more plainly: The four systems that lie in the body--digestive, circulatory, respiratory, and excretory--may be termed the nutritive systems, being designed for the maintenance and storage of life-forces. They are almost entirely under the control of the involuntary nerve centers, and have full and undisputed sway over life itself--that is, over the generating and storing of vital force, rather than over its usage.

SYSTEMS AND ORGANS OF THE BODY

=How the Body is Built.=--In a building such as the body it is well to begin with the unit--the building unit. In a house this is a brick or a stone; in all living structures, animal and vegetable, it is a cell.

All living structures, whether animal or vegetable, are built up of cells (which we shall consider in due course), and these cells are grouped together for different purposes to form different tissues. The tissues are the different materials of which the body is made. There are eight principal tissues in the body: bone, gristle, muscle, nerve, skin, fat, fiber, and connecting tissue.

(1) The Osseous, or bone tissue, is the framework of the body. This material is found, of course, in every part of the body and forms the skeleton.

(2) The Cartilaginous, or gristle, forms the joints of the body. This tissue covers the ends of the bones to form the joints; it unites the ribs with the breastbone; it forms the rings of the windpipe and the lid of the larynx at the back of the tongue; the lower part of the nose, the upper eyelid, and the ear.

(3) The Muscular, or muscle, forms the machinery of the body. This tissue covers all the bones with flesh, which is muscle, and is the chief part of a number of machines by which every movement is performed. It is also an important tissue in the wall of the abdomen and the floor of the chest.

(4) The Nervous, or nerve tissue, is the moving power of the body. It is the chief constituent of the brain and the spinal cord, inside the backbone or spine. It also forms the nerves, which run like white threads from the brain to all the muscles, and give them power to move.

(5) The Epithelial, or skin, forms the outer covering of the body. This tissue is the skin that covers the body outside, and lines it as mucous membrane inside, and also forms the teeth and nails.

(6) The Adipose, or fat, forms the under covering of the body. This tissue is the inner protective sheathing and padding of the body, beneath the skin, and round the internal organs. It consists of drops of oil, enclosed in separate cells.

(7) The Fibrous, or fiber or sinew, is the tissue that forms the cords and bands of the body. This tissue makes the strong tendons that fasten the muscles to the bones, and forms the covering or sheath of the bone itself, and the various organs.

(8) The Connective, or cementing tissue, joins all the parts and cells of the body together. This substance is found everywhere, all over the body, and is like the mortar in a house, fastening all the bricks together. It is a sort of network of cells and long fibers.

=Special Systems.=--These eight tissues are combined together into various groups of organs or systems for special purposes. These groups are six in number, and include: the circulatory, respiratory, digestive, excretory or secretory, locomotor, and nervous systems. There is also the reproductive system, which has to do with the propagation of the race, and involves many important and vital questions.

We may divide these six into three groups:

There are two in the chest:

(1) The Circulatory system is that by which the blood or liquid food is distributed throughout the body to all the tiny cells. This system includes the heart or force-pump, and the arteries, capillaries, and veins or the three kinds of pipes through which the blood travels.

(2) The Respiratory system is that by which we breathe, and by which the body is fed with oxygen, which gives the blood its bright red color. This system includes the nostrils and mouth, the windpipe and the lungs.

Then there are two in the abdomen, or stomach:

(3) The Digestive system, by which all the food is made into liquid and changed so as to nourish the body and pass into the blood. This system includes the mouth, gullet, stomach, liver, pancreas, intestines, and other organs.

(4) The Secretory, or excretory, system (for they are best grouped as one) manufactures the various fluids of the body, such as bile, urine, sweat, saliva, gastric juice, etc. It consists of various glands or secretory organs in different parts of the body, such as those in the skin, the kidneys, the lymphatic glands, the spleen, etc. It also gets rid of the refuse of the body.

Lastly, there are two in the head and limbs:

(5) The Locomotor system, by which all movement is effected. This includes the bones, joints, and muscles.

(6) The Nervous system, by which all the body is controlled, directed, and regulated. This system includes the brain, spinal cord, and the special senses, such as the ear, the eye, and all the nerves.

=The Human Chest, or Thorax.=--In it, the blood is purified and circulated. The thorax is closed above and below: above, by the neck, through which the windpipe enters it in front, conveying air to the lungs; and by the gullet behind, conveying food to the stomach. Below, the floor, dividing it from the abdomen beneath, is formed by a very large muscle stretching right across the body, called the Diaphragm, or partition wall; also called the Midriff. The thorax is walled in at the sides by the ribs, and behind by the backbone in which is the other tube that contains the spinal cord. The thorax contains the two organs of respiration and circulation.

The lungs are the organs of respiration. They are like two sponges filling the right and left halves of the chest. Wherever you can feel a rib there is part of the lung underneath. Each of these lungs is contained in a bag, like a skin, that separates it from the ribs, and is called the pleura (from pleuron = a rib), but the lung is not inside the bag.

The outer layer of the pleura is fixed to the side of the chest, the inner layer to the lung, and the two layers move on each other like a joint when we breathe.

The lungs are full of small air-cells with minute tubes leading from them. These gradually increase in size as they join together, till at last they unite in one large tube, or bronchus, for each lung. These two bronchi join together, and form the windpipe, or trachea, which conveys the air through the larynx into the mouth.

The windpipe is kept stretched widely open by a series of elastic rings of gristle. Behind the windpipe is the gullet, leading to the stomach.

We take air into the lungs to pass thence into the blood, and thus be carried to all the cells of the body to enable them to live and breathe.

=The Heart.=--The heart is at the lower part of the chest, between the two lungs. It is a fleshy or muscular organ, about the size of the fist--flat above, and pointed below like a sugar-loaf. It lies in a slanting direction behind the breastbone--the broad part, or the base, of the heart being upwards and partly to the right of the breast-bone; the point, or apex of the heart, being downwards and to the left, where it can often be seen beating against the chestwall.

The heart is hollow, and acts like a pump, forcing the blood all over the body through the great vessel that leaves the heart at the upper part. The heart, like the lungs, is enclosed in a double layer of folded bag, called the pericardium, because it is round the heart.

The gullet runs right down the back of the thorax, and passes out through the diaphragm, which forms the floor, into the abdomen.

The abdomen forms the lower half of the trunk, and is often called the stomach. It is full of organs belonging to the digestive system and secretory system, by which the fuel or food is rendered fit for use in the blood and the body.

The walls of the abdomen are not protected by ribs like the thorax, but are all formed of flesh or muscle. The principal organs they contain are the stomach, the liver, the pancreas, or sweetbread, the spleen or milt, the kidneys, the intestines, and the bladder.

=The Human Brain.=--The head and spine contain the principal nervous systems of the body and four organs of special sense--sight, hearing, smelling, and tasting.

The brain, which fills the head, consists of two parts: the Cerebrum, or greater brain, and the Cerebellum, or lesser brain, placed behind and below the larger one. From this brain, nerves run to every muscle of the body, enabling them to move the limbs and body as the mind directs; and another set of nerves run from every part of the body and skin to the brain, enabling the mind to know and feel all that goes on.

The brain is connected with the spinal cord by a flat band of brain matter, that lies on the inside of the occipital bone, called the Medulla Oblongata, or the Oblong Marrow. The spinal cord runs through a large hole in the occipital bone and right down the open tube formed by the spinal vertebræ, to the bottom of the backbone, and, all along its course, nerves leave it and enter it, as in the brain.

The organ of sight consists of the two eyes, which receive every image that we see, and transmit it to the brain. The organ of hearing consists of the two ears, by which we receive all the waves of sound that we hear, and transmit them to the brain. The organ of smell is in the upper part of the nose; the organ of taste at the hinder part of the tongue.

The organ of the voice is contained in the larynx in the neck, which joins the head to the body. Just under the chin in front of the neck you can feel what is called the Adam’s Apple, which is the front of the larynx, or voice-box, by which the air coming out of the lungs is formed into sounds.

The sounds are formed into words by the mouth, tongue, and teeth.

THE FIVE GATEWAYS OF KNOWLEDGE

These gateways--which we otherwise name the Organs of the Senses, and call in our mother speech, the Eye, the Ear, the Nose, the Mouth, and the Skin--are instruments by which we see, and hear, and smell, and taste, and touch: at once loopholes through which the soul gazes out upon the world, and the world gazes in upon the soul.

THE EAR: THE MARVELOUS ORGAN OF HEARING

The ear is divided into three parts:

(1) The external ear, made up of the outer portion and passage-way which leads up to the drum.

(2) The middle ear or drum, the continuation of the ear passage internal to the drum membrane, and

(3) The internal ear containing the labyrinth and the nerve of hearing.

DESCRIPTION OF THE EXTERNAL EAR

The outermost part, the skin-covered auricle, contains no bone, being simply a mass of cartilage covered by skin. It acts as a sound catcher and improves the hearing by directing sound-waves into the opening or external meatus. This meatus or passage-way runs directly inward for an inch and a half. The inner half of the passage-way runs through solid bone, ending abruptly at the membrane or sounding-board of the ear.

DESCRIPTION OF THE MIDDLE EAR

This part begins at the inner surface of the membrane, and extends inward for about a quarter of an inch. The outer surface of the membrane can be seen by the observer on pulling the top of the auricle or fleshy part of the ear a little upward, so as to straighten out the somewhat curved passageway or meatus. The membrane which is placed transversely across the meatus is whitish-pink or yellowish color.

WHAT THE MIDDLE EAR CONTAINS

The chief contents of the cavity of the middle ear are three tiny bones called the malleus or hammer bone, the incus or anvil bone, and the stapes or stirrup bone. In addition, an important nerve called the chorda tympani passes across the middle ear chamber. The three little bones contained in the middle ear may be looked upon as the connecting link between the outer ear, which gathers the sounds, and the internal ear, which transmits the effect of the sound waves to the brain, where they are translated into what we call hearing.

From without inward the three little bones lie touching each other, end to end, the outer end of the first bone being implanted between the layers of the drum membrane and the inner end of the innermost bone, fitting into a tiny opening which connects the middle ear with the internal ear. As the result of their lying touching each other, any movement of the ear drum caused by a sound wave striking against its outer aspect, moves the malleus bone; this, in turn, moves the middle incus, and this passes the movement on to the innermost part of the stirrup. This, in turn, passes the movement onward to the fluid or perilymph in the outermost part of the internal ear, and here the endings of the nerve of hearing receive the stimuli which we recognize as “sounds.” (See Plates.)

THE TWO IMPORTANT TUBES OF THE MIDDLE EAR

In addition to these contents of the middle ear there are also two tiny openings which, very necessary for health, are nevertheless sometimes a pathway by which serious disease may attack the ear and destroy the hearing. The first is a small passage-way leading from the upper part of the middle ear cavity through the bone to the mastoid antrum, a hollow space in the prominent mass of bone to be felt immediately behind the ear projecting outward and downward from the skull.

The second passage-way opening into the middle ear cavity is that of the Eustachian tube which leads directly to the back of the throat. The importance of this tube is that through it air can find its way directly into the middle ear, so that the air pressure on the two sides of the drum is always kept the same. If it were not for some such arrangement the pressure on the outer side of the drum would become greater than that on its inner surface. This would, of course, push the drum inward, and greatly reduce its mobility.

EXPLANATION OF THE INTERNAL EAR

This is a complicated structure of bony passages curled on themselves, roughly as in a snail shell, and lined with a delicate membrane. This membrane is, so to speak, floating in fluid. The layer of fluid between it and the bone is called the perilymph, while the two layers of the membrane enclose a similar fluid termed the endolymph. The internal ear or membranous labyrinth may be divided roughly into three chief parts: (1) the cochlea, the true organ of hearing; (2) the semi-circular canals, which control the act of balancing; and (3) the vestibule, or introductory chamber to the semi-circular canals.

The cochlea is a collection of three tubes curled up on themselves in snail-shell fashion.

The central canal of these three is the connecting link by which the sound waves, passed along over the three tiny bones--the malleus, incus, and stapes--finally reach the endings of the main nerve of hearing, the auditory nerve. (See Plate.)

THE EYE AND ITS WONDERFUL STRUCTURE

The human eye is a hollow globe containing fluids and the crystalline lens. Surrounded by its muscles it lies embedded in a cushion of fat in a conical bony hollow called the orbit. Through an opening in the bones making up the back of the orbit, the optic nerve leads from the back of the eye to the brain.

THE EYELIDS AND EYE-LASHES

The eyelids are made of layers of muscle and cartilage with an outer surface of skin and an inner surface which is a continuation of the conjunctiva that covers the eyeball. In the edge of the eyelid a series of tiny glands are embedded. The mouths of these open on the margin of the lids. The eye-lashes, whose duty it is to act as a screen, preventing foreign bodies such as dust or other air-born objects getting into the eye, are also inserted in the edge of the lid.

WHAT MAKES THE TEARS FLOW

About one-eighth of an inch from the internal angle of the eye, a small projection is to be seen on the margin of the lid. In the center of this is a tiny opening through which the tears as they collect in the eye are led away through two small canals to the lachrymal sac in the upper part of the nose. The lachrymal gland, which secretes the tears, or water, of the eye, is situated above on the outer side of the eyeball, between it and the bones of the orbit. The lachrymal gland is constantly secreting tears, which are carried by narrow ducts to the upper surface of the eyeball, whence they flow down over the eye, finally being collected at the inner corner of the eye and passing into the nose through the lachrymal punctures described above. Under certain circumstances, as from emotion, a blow, or the irritation of a cold wind, the tear fluid is secreted faster than it can escape through the punctures, and so flows over the lids and down the cheeks.

HOW THE EYE IS HELD IN PLACE

The eye is held in its socket or orbit by (1) the optic nerve, (2) by its six muscles attached to various points of its circumference, (3) by the conjunctiva, which is reflected off from its attachments to the outer coat of the eye directly on to the lids, and (4) by the eyelids themselves. (See Color Plate.)

HOW THE EYE IS CONSTRUCTED

The cornea is the transparent, bulging, central portion of the eye covering the pupil and the colored iris. Made of tiny transparent cells closely packed together, the cornea is not nourished by blood carried to it by the blood-vessels but by lymph which permeates through it in the tiny channels between the cells. By its curved surface it plays a part in focusing rays of light on to the lens situated just behind the iris.

Directly behind the cornea come the iris and pupil. The latter is nothing more than a hole in the center of the iris through which light enters the eye.

HOW THE LIGHT IS REGULATED

The iris is the screen of the eye. Just as the photographer uses a screen with a large opening when he wants more light to enter his camera and a small opening when he requires less, so Nature arranges that the iris automatically contracts or dilates to make a larger or smaller pupil opening, according to the amount of light needed within the eye for purposes of vision. When the light is very bright less is needed in the eye. Thus in brilliant artificial light at night one’s pupil is small. On the other hand, when the light is waning, as in the dusk or semi-darkness, the pupil is enlarged by the iris contracting down to a narrow ring under the outer circumference of the cornea.

WHAT DETERMINES THE COLOR OF THE EYE

The color of the eye depends on the position and amount of pigment cells in the iris. In the dark brown eye there is an abundance of pigment scattered through the substance of the iris as well as in the front layers nearest the surface. In the blue eye the pigment cells are buried deep in the iris and are fairly plentiful in amount. The colorless eye of the albino is the result of a deficiency of pigment in the iris.

The iris is fixed at its outer circumference, but its inner rim, which makes the border line of the pupil, is free, so that when the iris contracts the pupil becomes larger, since its inner free margin is drawn outwards toward the fixed outer margin. Close up against the deeper surface of the iris comes the crystalline lens.

WHY AND HOW WE SEE

The lens is a compact body of transparent cells, concave in form, and closely similar to the glass lens of a camera. The lens of the eye, however, differs from the camera’s glass lens because it changes its shape in focusing for objects at different distances. This focusing, which takes place automatically, is known as “accommodation.”

The object of the change in the shape of the lens is that no matter at what angle the rays of light reflected from the object looked at fall on the outer surface of the lens (through the opening in the iris), they may be accurately focused on the surface of the retina, or lining membrane at the back of the eye. When looking at a distant object the lens is fairly flat, because when in this position the rays of light will be accurately focused on the retina. If the eye is now turned to an object near at hand the rays of light from the object are more divergent than in the previous case, and if the lens retained its previous shape they would fail to be focused accurately on the surface of the retina. Hence Nature has arranged that the lens of the eye is elastic, automatically becoming flatter by the action of the ciliary muscle when distant objects are looked at and rounder or deeper when nearer objects are looked at.

EFFECT OF AGE UPON THE LENS

Up till middle age the eye retains in full this power of automatic accommodation. From middle age onward, however, the lens becomes less and less elastic. As a result the lens constantly remains more or less flattened. Although vision for objects at some distant from the eyes remains perfect, oldish people very frequently have to wear glasses (to correct the too great flatness of the natural lens) to obtain clear vision of objects close at hand.

WHAT HOLDS AND SURROUNDS THE LENS

The lens is slung in a ligament that is a part of the “ciliary body,” which is a continuation of the choroid coat of the eyeball. This ciliary body is a ring of tissue lying behind the iris connected with the anterior portion of the choroid coat of the eye.

Between the iris and the underlying lens on the one hand and the inner surface of the bulging cornea on the other is a small space or cavity filled with a clear transparent fluid called the aqueous humor.

THE COATS OF THE EYE

Looking at the white of the eye, the first coat is the transparent conjunctiva, which is reflected back on to the eyeball from the eyelids. Next comes the sclerotic coat, formed of dense whitish tissue, which seen through the transparent conjunctiva makes up the “white of the eye.” The sclerotic coat covers the whole globe of the eyeball with the exception of the transparent bulging cornea in front (which, however, is practically a continuation of the sclerotic), and the back of the eye where the optic nerve enters. The sclerotic is the thickest and densest coat of the eye.

Within the sclerotic coat, and so to speak lining it, comes the choroid coat. Countless blood vessels run through this coat, supplying both the one above it and that beneath it. As this coat approaches the front of the eye under the circumference of the cornea, it thickens into the ciliary body, forming a dense ring of tissues underneath the junction of the cornea and the sclerotic coat.

THE WORK OF THE RETINA

The innermost coat of the eye is called the retina. This coat contains the nerve endings of the optic nerve which, coming through the opening in the bony orbit, passes through the sclerotic and choroid coats. After entering the eye, the optic nerve divides into myriads of fibers, which, spreading from the point of entrance at the back of the eye, form a fibrous network all over its inner surface. In addition to this network of nerve fibers and highly specialized nerve cells, tiny blood vessels entering with the optic nerve branch out on all sides over the retina.

THE RODS AND CONES

The retina is a comparatively thick membrane composed of eight layers of different kinds of nervous tissue. The essential layer, that of the “rods and cones,” is the seventh from within outward. Thus a ray of light on entering the eye must pass through six superficial layers before it reaches the “rods and cones.”

The “rods and cones” are lying on a layer of colored or pigment cells whose duty it is to prevent diffusion of light within the eye. The eyeball, therefore, is to all intents a camera obscura, the iris representing the shutter, the crystalline lens the camera lens, and the layer of “rods and cones” the sensitive plate. When a ray of light falls on the layer of the “rods and cones,” this layer receives a nervous stimulus which is conveyed by the optic nerve to the brain. It is these sensations which the brain translates into what we term sight.

Where the optic nerve enters the back of the eye, there are no “rods and cones,” hence rays of light falling on this portion of the retina send no stimulus to the brain; in other words, images falling on the “blind spot” are not visible.

The “yellow spot” is a small area at the center at the back of the eye where the retina is very thin, consisting of little more than a single layer of “cones.” Images which fall upon this region are seen with the greatest distinctness.

HOW THE SENSE OF SIGHT IS PRODUCED

Sight is a nervous sensation due to the translation by the brain of the effects caused by rays of light being reflected from some object in front of the eye on to the innermost layer of the eye, the retina.

When an object is looked at, rays of light which reach the object from some source of light (such as the sun, a lamp, etc.) fall on the transparent outer part of the eye, the cornea. On account of its curved surface these rays of light are more or less bent inward so as to fall more or less perpendicularly on the forward anterior convex surface of the lens. If the light is weak or dim, the iris, which lies in front of the lens, will automatically contract down so as to make the opening by which the rays can enter the posterior chamber of the eye (the part behind the lens) as large as possible.

If the light is very bright the muscle fibers in the iris will relax so that the iris itself gets larger, and its central opening smaller, so that too much light may not enter. Passing through the lens the rays are focused by the lens so that they are brought together to a point exactly on the surface of the retina.

Here their presence has a certain effect on the rod and cone layer of the retina, the result of which is conducted along the optic nerve to the brain, where it is transformed into what we know as sight.

THE NOSE: ORGAN OF SMELL

The nose is composed partly of bone and partly of cartilage, the cartilages being firmly attached to the bones and to one another by fibrous tissue.

The bridge consists of the two nasal bones which are projections of the frontal bone of the forehead. From these are continued the nasal cartilages which form one-half to two-thirds of the external nose.

The interior is a large and complicated chamber divided into the right and left nares, or nostrils, by the partition called the septum. This, like the external part, consists of cartilage in front, attached to bone at the back.

=The Nostrils=, opening on the face in front, run backward for about two inches and open into the pharynx behind. But the single canal is divided into three separate passages some distance inward. This division is effected by the turbinated bones which jut out into the nostril and thus form the upper, middle, and lower air-channels. In this way the warm surface with which cold inhaled air comes in contact is greatly enlarged.

From the mouth cavity the nose is separated by the hard palate. On the external nose, scattered near the tip, are numerous hairs, sebaceous glands, and sweat glands. These glands are very liable to get blocked, giving rise to inflamed spots, and when hairs are pulled out small abscesses are apt to form.

=Membrane.=--The whole of the interior surface is lined with mucous membrane, and as this has a large area, and is very well supplied with blood, it raises the temperature of inspired air. The mucous membrane of the nose is continuous with that of the pharynx. Any inflammation, such as that which constitutes a “cold in the head,” is therefore extremely liable to extend backward and finally reach the bronchial tubes and lungs.

Over this membrane spread a multitude of small threads or nerves resembling the twigs of a branch; there are many such branches within the nostril, and they join together so as to form larger branches, which may be compared to the boughs of a tree. These finally terminate in a number of stems, or trunks, several for each nostril, which pass upward through apertures provided for them in the roof of the arched cavity, and terminate in the brain.

We have thus, as it were, a leafless nerve-tree whose roots are in the brain, and whose boughs, branches, and twigs spread over the lining membrane of the nostril. This nerve is termed the Olfactory.

When we wish to smell anything--for example, a flower--we close our lips and draw in our breath, and the air which is thus made to enter the nose carries with it the odorous matter, and brings it in contact with the ramifications of the nerve of smell. Every inspiration of air, whether the mouth is closed or not, causes any odorous substance present in that air to touch the expanded filaments of the nerve.

In virtue of this contact or touching of the nerve and the volatile scent, the mind becomes conscious of odor, though how it does so we know as little as how the mind sees or hears; we are quite certain, however, that if the olfactory nerve be destroyed, the sense of smell is lost.

Besides its endowment by the olfactory nerve, or nerve proper of smell, the nostril, especially at its lower part, is covered by branches of another nerve (known to anatomists as the fifth), of the same nature as those which are found endowing every part of the body with the susceptibility of heat, cold, smoothness, roughness, pleasure, and pain. It is on this nerve that pungent vapors, such as those of smelling-salts, strong vinegar, mustard, and the like, make the sharp impression with which all are familiar.

=Can the Sense of Smell be Educated?=--The extent to which the sense of smell may be educated far exceeds what most imagine can be realized from this sense. There are probably as many odors as there are colors or sounds; and the compass of one nostril in reference to the first, likely differs as widely from that of another, as the compass of the eye or the ear does in reference to the last two. The wine merchant, the distiller of perfumes, the manufacturer of drugs, the grower of scented plants, the epicure in things savory, the tobacco dealer, and many others, have by long training educated themselves to distinguish differences of odor which escape an uneducated and unpracticed nostril, however acute by natural endowment.

=Perfumes.=--Much importance attaches to the use of perfumes by both ancient and modern civilized nations. But all the ancient nations who had attained to civilization, were addicted to the use of perfumes to an extent to which no modern people at the present day affords any parallel. Not merely as contributing to the luxury of the body were perfumes so prized. They were used at every sacred ceremonial; lavishly expended at the public religious services; and largely employed at the solemn rites which were celebrated at the burial of the dead.

THE TONGUE: THE ORGAN OF TASTE

The organ of taste is generally held to be synonymous with the tongue, but, in reality, the throat and the nostril are as much concerned as the tongue in the perception of taste. The power of these portions of the body to distinguish savors mainly depends, as in the case of the eye and the ear, upon their connection with the brain through those fine white nerves which have been already referred to. The tongue and the auxiliary organs of taste are largely supplied with nerves, and through them those sensations are experienced which we connect with the words taste, savor, sapidity; sweet, salt, sour, bitter, and the like.

=Membrane of the Tongue.=--At certain points the membrane of the tongue forms distinct folds, containing fibrous or muscular tissue, which act to a certain extent as ligaments to the tongue. The most considerable of these folds is termed the frœnum (or bridle) of the tongue, and connects its anterior free extremity with the lower jaw. Other folds of mucous membrane pass from the base of the tongue to the epiglottis; while from the sides of the base, passing to the soft palate, are seen two folds on either side, the “pillars of the fauces.”

The upper surface of the tongue is divided into two parts by a long furrow, commencing at the tip, and extending back about two-thirds of the tongue’s length.

=Muscles of the Tongue.=--The muscles of the tongue are usually divided into two groups--viz.: the extrinsic muscles, which attach the tongue to certain fixed points external to it, and move it on them; and the intrinsic muscles, which pass from one part of the tongue to another, constitute its chief bulk, and move it on itself. These intrinsic muscular fibers run vertically, transversely, and longitudinally, and are so interlaced as mutually to support one another, and to act with the greatest advantage.

=The Bulbs of Taste.=--The mucous membrane is invested by stratified cells, which, over the surface of the tongue, cover little vascular projections termed, papillæ. At the back of the tongue are some eight or ten papillæ of quite a different nature, called “circumvallate.” They are arranged to form a V with its angle pointing backward. In the epithelium lining the trenches between the papillæ, curious little bodies called taste-bulbs are lodged. Each taste-bulb looks like a flask-shaped barrel or box, the walls of which are composed of flat elongated cells fitted side by side like the staves of a cask. The taste-bulbs open each by a little pore into the trench, and into the deeper part a nerve enters. The impressions are carried by the nerve directly to the brain in either the fifth or the ninth cranial nerves.

Before the substance can stimulate the terminals it is necessary for its aromatic principles to be in solution. This is generally effected through the agency of the saliva.

Four distinct gustatory qualities are appreciated by the sense of taste--sweetness, bitterness, acidity, and salinity. The intensity of the sensation of taste varies with (1) the area of the surface stimulated, (2) the concentration of the stimulant, (3) the length of the period of application, and (4) the temperature of the substance tasted. Tractile impressions, such as harshness, coolness, and astringency, are erroneously attributed to taste.

=Mis-Educated and Educated Taste.=--Of all the organs of the senses, that of taste is probably the one which receives the worst usage at our hands. The eye, the ear, and the nose are not educated at all, or their education is left to chance, but the tongue is deliberately mis-educated, perverted, and led astray. We eat what we should not eat; drink what we should not drink: eat too much of what we may eat, and drink too much of what we may drink. And the result is, that we ruin our health, enfeeble our bodies, dull our intellects, brutalize our feelings, and harden our hearts.

Yet assuredly taste has its legitimate domain, and it is as unworthy of man’s true dignity that he should be content to live upon the husks that the swine do eat, as that he should be miserable if he do not fare sumptuously every day. All the other senses have a direct interest in the practical decisions of the sense of taste. Drunkenness and dyspepsia dim the eye, dull the ear, blunt the nostril, and make the hand tremble.

=A Victim to the Other Senses.=--The sense of taste, in truth, is at the mercy of the other senses; and though it can revenge itself for their neglect or misuse of it, it is a sufferer by its own revenge.

Helpless, selfish, and exacting, the dependent of the other senses, and the servant of the body rather than of the soul, it frequently links us more with the lower animals than with higher existences, and has no element of ethereality about it.

A feast, indeed, may furnish pleasure to every sense, but it is usually not till hunger is appeased that the higher senses are ministered to. But the tongue, as the organ of taste, is the commissary-general, without whose supplies the other senses can achieve no conquests, and it is entitled to its share in the honors assigned to the united five; but its own sword is seldom drawn, and its aspect is not heroic.

THE HAND: CHIEF ORGAN OF TOUCH

The last of the bodily senses is Touch. It has the widest gateway, and largest apparatus of them all; for though we are in the habit of speaking of it as localized in the fingers, it reigns throughout the body, and is the token of life in every part. The nearest approach to death which can occur in a living body, is the condition of paralysis or palsy, a death in life, marked in one of its forms by the loss of that sense of touch which is so marked an endowment of every active, healthy creature.

The tactile susceptibilities of the skin depend, as do the peculiar endowment of the other organs of the senses, on its plentiful supply with those wondrous living nerves, which place in vital communication with each other all the organs of the body, on the one hand; and that, mysterious living center, the brain (and its adjuncts), on the other.

Our simplest conception of an organ of sense is supplied by the finger, which whether it touches or is touched, equally realizes that contact has been made with it, and enables the mind to draw conclusions regarding the qualities of the bodies which impress it. Now, after all, every one of the organs of the senses is but a clothed living nerve conscious of touch, and they differ from each other only in reference to the kind of touch which they can exercise or feel. Keeping in view that to touch and to be touched is in reality the same thing, so far as the impression of a foreign body is concerned, we can justly affirm that the tongue is but a kind of finger, which touches and is touched by savors; that the nostril is touched by odors; the ear by sounds; and the eye by light.

The Hand is emphatically the organ of touch, not merely because the tips of the fingers, besides being richly endowed with those nerves which confer sensitiveness upon the skin of the whole body, possess in addition an unusual supply of certain minute auxiliary bodies, called “tactile corpuscles,” but because the arrangement of the thumb and fingers, and the motions of the wrist, elbow, and arm, give the hand a power of accommodating itself spontaneously to surfaces, which no other part of the body possesses. Moreover, when we speak of the hand as the organ of touch, we do not refer merely to the sensitiveness of the skin of the fingers, but also to that consciousness of pressure upon them in different directions, by means of which we largely judge of form.

When a blind man, for example, plays a musical instrument he is guided in placing his fingers, not merely by the impression made upon the skin of them, but also by impressions conveyed through the skin to these little bundles of flesh called muscles, which move the fingers.

In many respects the organ of touch, as embodied in the hand, is the most wonderful of the senses. The organs of the other senses are passive, the organ of touch alone is active. The eye, the ear, and the nostril stand simply open: light, sound, and fragrance enter, and we are compelled to see, to hear and to smell; but the hand selects what it shall touch, and touches what it pleases. It puts away from it the things which it hates, and beckons toward it the things which it desires; unlike the eye, which must often gaze transfixed at horrible sights from which it cannot turn; and the ear, which cannot escape from the torture of discordant sounds; and the nostril, which cannot protect itself from hateful odors.

Moreover, the hand cares not only for its own wants, but, when the other organs of the senses are rendered useless, takes their duties upon it. The hand of the blind man goes with him as an eye through the streets, and safely threads for him all the devious ways; it looks for him at the faces of his friends, and tells him whose kindly features are gazing on him; it peruses books for him, and quickens the long hours by its silent readings.

It ministers as willingly to the deaf; and when the tongue is dumb and the ear stopped, its fingers speak eloquently to the eye, and enable it to discharge the unwonted office of a listener.

The organs of all the other senses, also, even in their greatest perfection, are beholden to the hand for the enhancement and the exaltation of their powers.

It constructs for the eye a copy of itself, and thus gives it a telescope with which to range among the stars; and by another copy on a slightly different plan, furnishes it with a microscope, and introduces it into a new world of wonders.

It constructs for the ear the instruments by which it is educated, and sounds them in its hearing till its powers are trained to the full.

It plucks for the nostril the flower which it longs to smell, and distills for it the fragrance which it covets.

As for the tongue, if it had not the hand to serve it, it might abdicate its throne as the “Lord of Taste.” In short, the organ of touch is the minister of its sister senses, and, without any play of words, is the handmaid of them all.

And if the hand thus munificently serves the body, not less amply does it give expression to the genius and the wit, the courage and the affection, the will and the power of man. Put a sword into it, and it will fight for him; put a plow into it, and it will till for him; put a harp into it, and it will play for him; put a pencil into it, and it will paint for him; put a pen into it, and it will speak for him, plead for him, pray for him.

What will it not do? What has it not done? A steam engine is but a larger hand, made to extend its powers by the little hand of man! An electric telegraph is but a long pen for that little hand to write with! All our huge cannon and other weapons of war, with which we so effectually slay our brethern, are only Cain’s hand made bigger, and stronger, and bloodier!

What, moreover, is a ship, a railway, a lighthouse, or a palace--what, indeed, is a whole city, a whole continent of cities, all the cities of the globe, nay, the very globe itself, in so far as man has changed it, but the work of that giant hand, with which the human race, acting as one mighty man, has executed its will!

What an instrument for good it is! What an instrument for evil! and all the day long it never is idle. There is no implement which it cannot wield, and it should never in working hours be without one. It is the one universal craftsman. For the queen’s hand there is the scepter, and for the soldier’s hand the sword; for the carpenter’s hand the saw, and for the smith’s hand the hammer; for the farmer’s hand the plow; for the miner’s hand the pick; for the sailor’s hand the oar; for the painter’s hand the brush; for the sculptor’s hand the chisel; for the poet’s hand the pen; and for the woman’s hand the needle.

For each willing man and woman there is a tool they may learn to handle; for all there is the command, “Whatsoever thy hand findeth to do, do it with all thy might.”

Such are the five entrance-ways of knowledge, which John Bunyan quaintly styles Eye-gate, Ear-gate, Nose-gate, Mouth-gate, and Feel-gate.

BOOK OF BIOGRAPHY

I. CLASSIFIED BIOGRAPHICAL CHART BY CENTURIES:

CHRONOLOGICAL ARRANGEMENT OF THE GREAT MASTERS OF ACHIEVEMENT FROM THE EARLIEST TIMES TO THE PRESENT

THE WORLD’S IMMORTALS: IN RELIGION AND MORAL REFORM, GOVERNMENT, LITERATURE, FINE ARTS, PHILOSOPHY AND EDUCATION, SCIENCE, AND INDUSTRY.

THE WORLD’S LEADERS TO-DAY

II. PRONOUNCING DICTIONARY OF BIOGRAPHY: CHRONOLOGICALLY ARRANGED BY CENTURIES

III. MISCELLANEOUS TABLES AND CHARTS

(Biographical Chart only included in Single Volume Edition.)

=THE WORLD’S IMMORTALS AND MASTERS OF ACHIEVEMENT IN RELIGION, GOVERNMENT, LITERATURE, FINE ARTS, PHILOSOPHY, SCIENCE AND INDUSTRY--TABULATED BY CENTURIES AND CLASSIFIED=

NOTE--The names of the world’s greatest masters are set out in CAPITALS in the respective columns. In general the names are placed in the centuries associated with the greatest achievements of each individual.

+------+--------------------+--------------------+--------------------+ | =Cen-| =Fine Arts= | =Philosophy and | =Science and | | tu- | | Education= | Industry= | | ries=| | | | | | Architects, | Philosophers, |Inventors, Discover-| | |Sculptors, Painters,| Educators, | ers, Engineers, | | | Musicians | Psychologists, | Naturalists, Physi-| | | |Moralists, Logicians| cists, Mathemati- | | | | | cians, Chemists, | | | | | Physicians, | | | | | Biologists | +------+--------------------+--------------------+--------------------+ | =4000|Early architecture, |Philosophy had its |Astronomy was the | | B. C.|sculpture and paint-|rise among the Egyp-|first science culti-| | to |ing made notable ad-|tians and Hindus, |vated in the world. | | 1000 |vances under Babylo-|followed by the |It was known to the | |B. C.=|nians, Assyrians, |Greeks. |Babylonians, Assyri-| | |Egyptians and | |ans, Egyptians, | | |Hindus; but no great| |Greeks and Chinese. | | |individual names | | | | |were connected with | | | | |it until the time of| | | | |the Greeks. | | | +------+--------------------+--------------------+--------------------+ | =1000|... |... |... | | B. C.| | | | | to | | | | | 700 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _7th |... |... |... | | Cent.| | | | |B. C._| | | | | | | | | | =700 | | | | | B. C.| | | | | to | | | | | 600 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _6th |... |Thales, Greek phi- |... | | Cent.| |losopher. | | |B. C._| | | | | | |Pythagoras, Greek | | | =600 | |philosopher. | | | B. C.| | | | | to | | | | | 500 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _5th |Zeuxis, Greek |SOCRATES, Greek phi-|Hippocrates, Greek | | Cent.|painter. |losopher. |physician. | |B. C._| | | | | |PHIDIAS, Greek | | | | =500 |sculptor. | | | | B. C.| | | | | to |Ictinus, Greek | | | | 400 |architect. | | | |B. C.=| | | | | |Polycletus, Greek | | | | |sculptor and | | | | |architect. | | | +------+--------------------+--------------------+--------------------+ | _4th |Apelles, Greek |PLATO, Greek philos-|EUCLID, Greek geo- | | Cent.|painter. |opher. |meter. | |B. C._| | | | | |Praxiteles. |ARISTOTLE, Greek | | | =400 | |philosopher. | | | B. C.| | | | | to | | | | | 300 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _3rd |... |Epicurus, Greek phi-|Archimedes, Greek | | Cent.| |losopher. |mechanician. | |B. C._| | | | | | |Zeno, Greek Stoic | | | =300 | |philosopher. | | | B. C.| | | | | to | | | | | 200 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _2nd |... |... |... | | Cent.| | | | |B. C._| | | | | | | | | | =200 | | | | | B. C.| | | | | to | | | | | 100 | | | | |B. C.=| | | | +------+--------------------+--------------------+--------------------+ | _1st |... |... |STRABO, Greek geo- | | Cent.| | |grapher. | |B. C._| | | | | | | | | | =100 | | | | | B. C.| | | | | to | | | | | 1 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _1st |... |EPICTETUS, Roman |Pliny (Plinius), the| | Cent.| |Stoic philosopher |elder, Roman natu- | |A. D._| |(60-120?). |ralist (A. D. 23- | | | | |79). | | =1 | | | | | A. D.| | | | | to | | | | | 100 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _2nd |... |MARCUS AURELIUS |CLAUDIUS PTOLEMY, | | Cent.| |ANTONINUS, Roman |Græco-Egyptian as- | |A. D._| |emperor, philosopher|tronomer, geographer| | | |(121-180). |(2d C. A. D.). | | =100 | | | | | A. D.| | |Claudius Galen, | | to | | |Roman physician and | | 200 | | |medical author (130-| |A. D.=| | |200?). | +------+--------------------+--------------------+--------------------+ | _3rd |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =200 | | | | | A. D.| | | | | to | | | | | 300 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _4th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =300 | | | | | A. D.| | | | | to | | | | | 400 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _5th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =400 | | | | |A. D. | | | | | to | | | | | 500 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _6th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =500 | | | | | A. D.| | | | | to | | | | | 600 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _7th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =600 | | | | | A. D.| | | | | to | | | | | 700 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _8th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =700 | | | | | A. D.| | | | | to | | | | | 800 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _9th |... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =800 | | | | | A. D.| | | | | to | | | | | 900 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _10th|... |Avicenna, Mohammedan|... | | Cent.| |physician and phi- | | |A. D._| |losopher (980-1037).| | | | | | | | =900 | | | | | A. D.| | | | | to | | | | | 1000 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _11th|... |... |... | | Cent.| | | | |A. D._| | | | | | | | | | =1000| | | | | A. D.| | | | | to | | | | | 1100 | | | | |A. D.=| | | | +------+--------------------+--------------------+--------------------+ | _12th|... |Pierre Abelard, |... | | Cent.| |French scholastic | | |A. D._| |and logician (1079- | | | | |1142). | | | =1100| | | | | A. D.| |Averroës, Arabian | | | to | |philosopher and | | | 1200 | |physician (1149?- | | |A. D.=| |1198). | | +------+--------------------+--------------------+--------------------+ | _13th|GIOVANNI CIMABUE, |Albertus Magnus, |ROGER BACON, English| | Cent.|father of modern |Bavarian philosopher|monk and scientist | |A. D._|painting, Florentine|and schoolman |(1214-1294). | | |painter (1240?- |(1193?-1280). | | | =1200|1302?). | | | | A. D.| |John Duns Scotus, | | | to |Nicola Pisano, |Scotch scholastic | | | 1300 |Italian sculptor |theologian (1265?- | | |A. D.=|(1200?-1278). |1308). | | | | | | | | | |SAINT THOMAS | | | | |AQUINAS, Italian | | | | |scholastic philos- | | | | |opher (1225-1274). | | +------+--------------------+--------------------+--------------------+

=THE WORLD’S IMMORTALS AND MASTERS OF ACHIEVEMENT IN RELIGION, GOVERNMENT, LITERATURE, FINE ARTS, PHILOSOPHY, SCIENCE AND INDUSTRY--TABULATED BY CENTURIES=

BOOK OF THE CHILD WORLD

PHYSICAL LIFE OF CHILDREN: WORK AND PLAY

THE CHILD, THE PARENTS AND THE SCHOOL

THE MENTAL LIFE OF THE CHILD: STORY-LAND, NATURE-LAND, SCHOOL-LAND

SIMPLE LESSONS: WORDS, READING, WRITING, NUMBERS, ETC.

THE MORAL LIFE OF THE CHILD: CONDUCT, MANNERS AND ETIQUETTE, ADOLESCENCE, HABITS, CULTIVATION OF IDEALS, ETC.

MANHOOD, WOMANHOOD, PARENTHOOD

(Abridged in Single Volume Edition.)

THE CHILD WORLD

THE GROWING BODY -- WORK AND STUDY -- FOOD -- THE NERVOUS SYSTEM -- PUBERTY -- REST AND SLEEP -- THE EYE -- THE EAR -- OTHER SENSES

THE HEALTH OF CHILDREN DURING SCHOOL LIFE

Children begin school life at an age which is, unfortunately, one of the greatest importance in their physical development. It is a truism that no mechanism, whether animate or inanimate, can do two things at once and get as good results as when all its efforts are being directed toward one object. So it is obvious that any vital energy used in developing a young child’s brain must be taken away from the amount that had hitherto been entirely devoted to physical growth. Too often this fact is lost sight of both by energetic teachers and ambitious parents.

Instead of being delighted with the rapid development of the child’s mind, parents should receive any evidences of abnormal advancement with some suspicion of its true worth.

WHEN THE CHILD FIRST GOES TO SCHOOL

At the age of six, when the average child first goes to school, practically everything he sees is new and interesting, and worthy of deep consideration. His brain gets no rest from the time he wakes until he goes to sleep at night.

To do its work, the brain needs a full and active blood supply, and this it will take often at the expense of leaving an inadequate amount for the demands of the rest of the body.

Curiously enough, excessive mental activity seems to have no stunting effect on the growth in the way of height. It is in breadth and thickness that the body suffers. Everyone is familiar with the tall, lanky boy or girl in the early teens who is said not to care much for games and exercise, and is, unfortunately, “rather delicate.” This youngster is almost certain to be pointed out by the proud parents as being extremely well up in his studies.

Short of encouraging laziness or indolence at school, it really makes very little difference to the ordinary man or woman, so far as their adult mental attainments go, whether they were ranked as fairly good scholars or fairly poor ones when they were young children. On the other hand, the effort necessary to be made by a sensitive, not over-brilliant child to keep a good place among its fellows may have a serious physical effect that will hamper him or her throughout life.

The effort should be made when a child is first sent to school to determine just how much work he can do comfortably and happily. If an attempt is made to force him to do more than this, he will become depressed and worried. With children, any mental worry will shortly produce unmistakable signs on the physique. It is a bad plan to attempt to get as much as possible out of a child; there should always be a certain amount of vital energy left for emergencies.

IMPORTANT CONDITIONS AFFECTING THE CHILD’S LESSONS

With young children, no lesson should last for more than half an hour, and if possible, a short interval between each lesson should be spent in the open air. If the young scholar is notably in advance with his school work, discourage this; or, at any rate, carefully consider whether his health will allow such active development. If backward and seemingly lazy, the cause of the indolence should be sought first in the physical condition before the character is assailed.

Above all, no child under fifteen should have to do any routine night study to keep up in his lessons. Young eyes are easily strained, and young bodies are easily tired. Watch a tired child who has to study at night; he will get his body in the most comfortable position he can manage, and will take no thought of the direction from which the light falls on his page. Nor has he the energy to hold his book so that the plane of the lines is always parallel to that of his eyes.

His mind may accumulate a little extra book knowledge by such work, but only at the risk of strained eyes and possible spinal defects. Lateral curvature of the spine, in a great majority of cases, may be traced back to habitual faulty postures used by children when at school work. A fair rule to make about night work is to allow a child to study at home only so long as he will comfortably sit upright and hold his book at a correct angle.

In children, the physical state is a very good guide to the mental condition. If the body is tired, the mind is in no fit state to absorb knowledge. The thin, narrow-chested, delicate youth, perhaps with strained eyes and nearly always with a good school record, is nine times out of ten a preventable mistake.

If, when first he showed signs of more than average scholarship, his parents had noted that this superiority was due principally to work done when physically tired, and to neglect of outdoor games and general “play,” a little sense of the comparative worth of health and youthful scholarship would have given him a greater chance of developing into a valuable citizen.

THE PROPER TIME FOR WORK

A child’s brain, and its body as well, are in the prime of their vigor during the morning hours. From nine till noon, therefore, should be the period of the hardest mental or physical work he undergoes. Evening preparation of lessons is harmful, not only because it tends to bring into a state of high activity the brain, which shortly should be quiet and ready to sink into slumber, but also because it throws hard work on an already fatigued organ. Much of the nervousness, debility, and insomnia so common among school children can be traced to evening preparation.

NECESSITY OF ABUNDANT FOOD

The more actively growing the tissues, the greater the need for abundant nourishment. The growing child, therefore, requires more food in relation to his size and weight than does the grown person who has passed the stage of rapid development.

No fixed rule can be laid down as to how much a child should eat. Generally speaking, the country-bred child, living an outdoor life, may rely on his own appetite as a guide. On the other hand, the city child, living a more indoor artificial life, may have little appetite, and as a result, if not watched, may lapse into a condition of malnutrition simply through underfeeding. The best guide, perhaps, is the child’s weight. If he is continually below weight, this fact may in all cases be taken as proof either that the child’s food is unsuitable to its age and digestive powers, or else deficient in amount.

EFFECT OF THE SEASONS ON THE NERVOUS SYSTEM

The effect of the change in seasons is much more marked in children than in grown people. In the Spring in particular the watchful mother should keep a careful eye on the health of her little ones. “There come with the Spring in many children,” writes a noted physician, “a restlessness and excitability, a perversity and irascibility of temper, or a listlessness, and indisposition for exertion that are not displayed at other times; and there come then, also, more plentifully than at other seasons, physical indications of debility and the scrofulous habit, such as enlarged glands and tonsils, dyspepsia and loss of appetite, strumous ophthalmia, discharges from the ear, and enlargements of joints.”

The moral is that since the body is growing fastest (and therefore has the greatest need of husbanding its vitality) in the Spring time, any extra pressure on the nervous system as from prolonged school hours, or any undue exertion, should be strenuously avoided. Unfortunately with the “final” examinations in the early summer, our school systems demand that the hardest and most strenuous work of preparation falls in the Spring time, the season at which the body is least fitted to withstand abnormal stress.

When a child or growing boy or girl becomes more nervous in the Spring time than is his usual habit, or becomes depressed in mind, or constantly complains of being tired, the only common-sense treatment is to put an end at once to all schooling for the time being, and to turn the child out-of-doors every day for all the hours of sunlight.

THE PERIOD OF PUBERTY AND ITS SPECIAL PROBLEMS

Parents should ever be watchful regarding the education of their young children when they approach the age of puberty, that is, the period when the child begins to develop into the man or woman.

Profound and rapid changes take place at this period in mind, brain, the nervous system, the glandular system, and, one may indeed say, in the body generally. The nerve centers temporarily lose some of their normal stability, and such conditions as insanity, hysteria, and epilepsy, rare in childhood, now become common. Even though no actual nervous disease develop, there is quite commonly during this change from childhood to adult life a period of nervous excitability and exhaustion accompanied by physical weakness, which to a great extent unfits the young person for close pursuit of his or her studies. Particularly in young girls is there the greatest necessity for curtailing any tendency to overwork at school during this period.

CONDITIONS OF BONES AND MUSCLES AT THE PERIOD OF PUBERTY

At this time there is also rapid growth and development of the bones which lengthen rapidly, and are still soft and cartilaginous in places. It is all-important at this period, therefore, that the muscles on the two sides of the body receive roughly the same amount of use, otherwise there is grave danger of some deformity, such as lateral curvature of the spine, developing.

While the bones are in this condition of rapid development, all muscle-straining attitudes, such as sitting upright at a desk, practicing at the piano, writing, painting, etc., should be kept within such limits as never to entail real fatigue. Young girls at this period, even more than boys, require all their strength and vitality to support them in their rapid growth. This does not mean, however, that all muscular exercises must be forbidden during the period of puberty, which may be reckoned as from twelve to sixteen in girls, and from thirteen to sixteen in boys. The point is that violent, really fatiguing exercise, such as hockey, hunting, cycling tours, mountain climbing, etc., as well as all occupations which entail the holding of the muscles tense and fixed in one position for a long period, should be indulged in very sparingly, if at all. The young girl can obtain all the exercise necessary for health in less strenuous outdoor pursuits such as golf, croquet, a little not too strenuous tennis, walking, etc.

GENEROUS HOURS OF SLEEP SHOULD BE ALLOWED

While moderate mental work does not in the healthy grown person necessitate an increase in the amount of sleep, the child at school, constantly using his brain in the accumulation of new ideas, needs an even more generous proportion of sleep than if his brain were not so occupied. Again, if the child shows any signs of nervousness, he ought to be allowed to sleep a little longer than the more stolid non-temperamental child. The following is the average duration of sleep required at different ages:

4 years of age 12 hours 7 years of age 11 hours 9 years of age 10-1/2 hours 14 years of age 10 hours 17 years of age 9 hours

Up to the approach of puberty (the change from childhood to adult life) a child may well be allowed to sleep a little later in the morning in the winter than in summer. Again, if as is frequently the case, he should suddenly commence to grow in height very rapidly an extra hour or half-hour in bed may be of the greatest service in weathering the strain of the rapid growth.

PRECAUTIONS TO PREVENT SLEEPLESSNESS

Insomnia is sometimes very troublesome in young children, demanding most painstaking treatment. Most important in encouraging the habit of going to sleep immediately on being put to bed is regularity in the hour of bedtime. Unless the child is put into bed at a certain fixed hour with clock-like regularity, the habit of getting sleepy (which is such an important factor in going to sleep) cannot be normally developed.

Sometimes a subdued, shaded light will sooth a nervous child’s excited brain and so induce sleep. A child who wakes in terror in a pitchdark room may for years be nervous about going to bed in the dark. Any attempt to stamp out this tendency to nervousness by refusing a comforting glimmer of light in the room may bring on a habit of sleeplessness on first going to bed which may be difficult to eradicate. Sometimes a softly-ticking clock, by affording a sense of companionship, encourages the child to drop off to sleep.

MENTAL QUIETUDE AND GOOD VENTILATION

Another factor in encouraging sleep is a quiet mental state, which is best brought about by the strict avoidance of all exciting games or other mental activities for at least an hour before bedtime. School lessons prepared in the evening are a fertile source of insomnia in children. The brain, keyed up to working at full pitch, cannot quiet down at its owner’s wish, and its unwonted activity may banish sleep for an hour or more.

While free ventilation is essential in the child’s sleeping-room, it should never be forgotten that the young are more susceptible to cold than are grown people, and have not the same power of generating extra body heat to replace any undue loss of warmth from exposure to outside cold. The temperature of the child’s bedroom, therefore, should be kept between 55° and 60° F. If below this, a general feeling of chilliness, and in particular of cold feet, may be the cause of sleeplessness.

Apart from the discomfort and misery caused by the feelings of chilliness, cold feet lead to the adoption of postures in bed which are anything but conducive to health.

BENEFICIAL EFFECTS OF THE BATH

In nervous children who sleep badly, a hot bath or a hot mustard foot bath often acts like a charm, the child falling into deep sleep almost as soon as it has been tucked in bed. The warmth, by dilating the blood-vessels, on the surface of the body in the case of the full bath, or of the feet in the case of the mustard foot-bath, draws blood away from the brain and so, reducing its activity, allows it to quiet down into sleep.

Where did you come from, baby dear? Out of the Everywhere into here. Where did you get those eyes so blue? Out of the sky as I came through. What makes the light in them sparkle and spin? Some of the starry twinkle left in. Where did you get that little tear? I found it waiting when I got here. What makes your forehead so smooth and high? A soft hand stroked it as I went by. What makes your cheek like a warm white rose? I saw something better than anyone knows. Whence that three-cornered smile of bliss? Three angels gave me at once a kiss. Where did you get this pearly ear? God spoke, and it came out to hear. Where did you get those arms and hands? Love made itself into bonds and bands. Feet, whence did you come, you darling things? From the same box as the cherubs’ wings. How did they all just come to be you? God thought about me, and so I grew. But how did you come to us, you dear? God thought about you, and so I am here.

(The above poem was written by George MacDonald, Scottish novelist and poet; born 1824, died 1905. He wrote a long list of novels, stories and poems. His children’s poems and stories are deservedly popular, and contain numerous passages of singular beauty, lighted up with fine fancy and descriptive power.)

HOW TO TEACH A CHILD TO READ AT HOME

Aa Ee Ii Ll Pp Ss Ww

Bb Ff Mm Tt Xx Jj Qq Cc Gg Nn Uu Yy

Dd Hh Kk Oo Rr Vv Zz

Above are the big and little letters of the Alphabet.

Below is a story with all these letters in words.

I saw the big ox when I went to the Zoo last week. It was in a den by the cave and stood near the bars. I thought it looked quite fierce when it stared at me. It made me jump when it put its nose out of the bars. A man fed the ox with some hay that he got from a box. It then lay down on the hard floor and had a nap. I should not like to be in the den with the ox.

It is not a proper test of a child’s advance that he should be able to read very early. Neither do we now make the teaching of reading the chief object in first lessons. Rather does the child learn first to master the difficult art of connecting spoken sounds with written signs somehow, on the happy road from babyhood to schooldays, while his mother still holds him by the hand.

The training of your boy’s ear in detecting the sounds that go to make up the words he uses is of the very first importance. You encourage him in the use of language by getting him to talk freely about what you do together, describing in his own pretty way the flowers, birds, toys, pictures that he loves. All the time you are gently insisting on perfect pronunciation, clear, pleasant modulation of his speaking voice, quiet breathing through the nose. Presently, when you see he is quite ready for it, you lay stress on the sounds made at the beginning and end of such words as cat, dog, puss, pig. He will soon copy quite accurately the sounds of the various consonants, and find other words beginning or ending with similar sounds to those in the examples you give.

Later will come the vowel sounds, and patient work will be needed to make him see the difference in the various sounds of a, o, and so on. At this stage it will amuse him to have a looking-glass before him to see how the shape of his mouth alters when speaking. Let him practice working the muscles round his lip and moving his tongue freely. It will also help if he sings the vowels, thus--take deep breath, sing a (as in father) as long as the breath lasts; take breath, sing a (as in fate), in same way; and so on with all the vowel sounds.

You will, of course, make a table of all the sounds you teach him for your own use, with lists of suitable words, and something has really been accomplished in the numberless five-minute sound-lessons when the child can break up the words he uses into the sounds that go to make them--b-u-n, bun; f-i-g, fig.

So much for the first training in recognizing and reproducing the sounds.

And now we come face to face with the much-discussed question--when and how is a child to learn the letters (the printed signs of sounds) and the names given to these letters? Some children settle this question for themselves by “picking up” these letters and their names from picture-books and blocks with little outside help, but they will find it useful later on to know the names of the letters and the order of the alphabet. See to it that your boy learns to call the letters by their sounds, not their names, and help him to realize that the letters are the signs of the sounds, used to tell us what sounds we are to utter.

You have a sand-tray? Let the fat little finger practice making a round o in it, while the rosy lips form the long o, as in n_o_ and l_o_rd, the short sound, as in n_o_t; or tracing crooked s while he hisses like the geese on the common, or says “puss,” “sat,” and so on.

If you have a box of good, plain letters, let him pick out the m in _m_ouse, the t in table and in ra_t_. Your small blackboard will come in handy, for he will be most happy to print on it in chalks the letters as he learns them. Let him model their shapes in clay, draw and paint them in colors, make them out of slips and curves of colored cardboard, varying the practice as much as possible; and see to it that he is never bored. He will soon greatly enjoy identifying and cutting out large and small letters as he learns them from advertisements in big type, and pasting them in a “letter” scrapbook, made by fastening together a few sheets of brown paper. Guide him to class together v and f, r and l, s and z, b and p, m and n, t and d, and the vowels in their order, with a whole page to themselves--this with a view to the time when he begins to study seriously.

But that is looking far ahead. We have now brought him to the point of being ready for his first reading lesson. But do not hurry; give his eyes plenty of distance work, plenty of training in reading Nature’s wide-open book, before you put printed books into his hands. He is to be a keen lover of books, so make him want to read, and see to it that he is interested and happy every moment of the time given to his reading lesson.

Here is the method:

Buy three copies of some well-printed simple stories; put one copy aside, and cut up the other two, pasting the sheets on drawing-paper, alternate pages face down, so that you get one complete copy out of the two books.

Now cut up, line by line, and then word by word, the first little story, and put the words in a small tray or box. Perhaps it is, “Thank you, pretty cow.” So now print on your blackboard two or three of the words--cow, milk, pretty, the child earnestly watching and listening while you say the words very distinctly, giving the component sounds as clearly as you possibly can.

Then hand him the tray, and let him pick out the words and name them as you have done. Proceed in the same way with a few more words of the story, printing them as you go in a column on the board, and when he knows them up and down, in and out, the great moment has arrived. Your heart will beat as you put the little book--the copy that was not cut up--into his hands. He can read, so much at any rate, quite readily.

Note that there must be no spelling; it is “look and say.” Next day you take word-building with the box of letters, and a fine game you have, based on the words learned the day before. Add letters and syllables in every way you can think of, always giving sounds, not names; let the boy read, copy, take from dictation these new words for a happy twenty minutes. He is now learning to spell, that he may be able to write with the sound signs. Go on like this, reading one day, word-building the next, till several sets of little books have been used up.

Let him dramatize the little stories and poems whenever you can; take parts with him, thus laying the foundation of real, live reading aloud, without any disfiguring mannerisms or self-consciousness. His stock of words grows apace--ten a day will give over three thousand in a year--and little by little, as opportunity offers, the more complex sounds in our language and its puzzling irregularities are unfolded and made familiar. Thus reading, elocution, spelling, writing, all advance together.

[Illustration: =THE CHILD’S PICTURE GRAMMAR--NOUNS AND VERBS=

A NOUN IS THE NAME OF ANY THING--A VERB TELLS WHAT A NOUN DOES OR IS DONE TO

THE HORSE STOPS

THE FISH SWIMS

THE BOY HOPS

THE BIRD SKIMS

THE RAIN FALLS

THE BABE CRIES

THE MAN HAULS

THE BEE FLIES

BALLOONS RISE

ACORNS DROP

THE WOMAN BUYS

AIRGUNS POP

THE CART IS DRAWN

THE HOOP IS ROLLED

THE SHEEP IS SHORN

THE LAWN IS ROLLED

THE DOG IS LED

THE PIG IS DRIVEN

THE LION IS FED

THE PRIZE IS GIVEN

THE FIRE BURNS

THE WATER FLOWS

THE BOAT TURNS

THE TRAIN GOES]

[Illustration: =WHAT OUR DOMESTIC ANIMALS GIVE US=

THE USEFUL THINGS OBTAINED FROM THE COW, HORSE, SHEEP, GOAT, PIG, FOWL, AND DEER

MILK

BUTTER

CHEESE

BEEF

LEATHER

KNIFE-HANDLES

COMBS

BUTTONS

SOAP

JELLY

GLUE

CHAIR-COVERS

HAIR FOR STUFFING SOFAS

PLUMES

CATGUT

SOCKS

MUTTON

WOOLLEN GOODS

RUGS

BOOK COVERS

CARPETS

MILK

PERSIAN SHAWLS

WIGS

SHOE-LACES

GLOVES

KNIFE-HANDLES

BOOK COVERS

WATER SKINS

PORK

BACON

LEATHER GOODS

BRISTLES

LARD

BLADDERS

GLYCERINE

EGGS

FLESH

FEATHERS FOR BEDS AND PILLOWS

FEATHERS FOR HATS

KNIFE-HANDLES

GLOVES

HAIR FOR STUFFING SADDLES

VENISON]

THE STORY OF THE SPIDER AND THE BUTTERFLY

On the garden wall a brown [Illustration: Spider] was spinning her [Illustration: Web]. Backwards and forwards she went, making hundreds of little threads at once, twisting them into white ropes, arranging them with her feet and the little hooks on her jaws, and gluing them together where they crossed.

The [Illustration: Butterfly] stood on a [Illustration: Leaf] and watched.

“Is that to put your eggs in?” she asked at last. “Or do you put them on a cabbage?”

“On a cabbage! No, indeed!” said the [Illustration: Spider], staring with all her eight eyes at once. “I make a soft nest of silken threads to put them in.”

“That would not do for my babies.” And the [Illustration: Butterfly] nodded her head and looked very wise. “They would get their wings fast in the threads.”

“Their what?” gasped the [Illustration: Spider], standing suddenly still in the middle of her [Illustration: Web].

“Their wings,” repeated the innocent [Illustration: Butterfly]. “I don’t think I dare let my children come to play with yours if you always hang [Illustration: Nets] about.”

“But your children won’t have wings!” gasped the [Illustration: Spider] again. “They won’t be baby [Illustration: Butterflies]!”

The [Illustration: Butterfly] laughed gaily.

“What a funny idea!” she said. “Your eggs hatch into baby [Illustration: Spiders], don’t they? and they don’t have wings. And the hen’s [Illustration: Eggs] hatch into little baby [Illustration: Chickens], and they do have wings, like the hen. I saw them this morning running after her, with all their wings stretched out. I suppose they are not old enough to fly yet. When my babies can fly, I shall go back to the flower garden.”

She flew away, leaving the astonished [Illustration: Spider] still sitting in the middle of her [Illustration: Web] trying to understand it all.

“Well!” she exclaimed to herself at last. “That’s what comes of having no mother! I always did say that the family arrangements of the [Illustration: Butterflies] are the most foolish I ever heard of.”

The [Illustration: Butterfly] was very busy, gumming her eggs safely underneath a cabbage leaf. Each little jar hung by its narrow end, as close to the next as could be.

“What a funny old [Illustration: Spider]!” she thought at last, when she had finished. “I wonder if she has finished that [Illustration: Web].”

“Have you found a cabbage to please you?” called the [Illustration: Spider].

“Well, I suppose it’s all right,” answered the [Illustration: Butterfly] a little doubtfully. “I don’t seem to be able to think of a better place to put my eggs, and I suppose the flowers will grow on the cabbage very soon. My baby [Illustration: Butterflies] will not be able to fly far at first to find honey.”

“You mean your creepy, crawly [Illustration: Caterpillars]!”

“Don’t you mean [Illustration: Spiders]?” asked the [Illustration: Butterfly], trying to be sarcastic.

“Nothing so sensible! If you want to see----”

“Hush! hush! Don’t quarrel!” said the Breeze, shaking the [Illustration: Spider]’s [Illustration: Web] and puffing at the [Illustration: Butterfly]’s wings.

“She says that my babies will be creepy, crawly----”

“Come away! come away! Come and find some honey!” said the Breeze.

He shook the [Illustration: Leaf] and the [Illustration: Butterfly] fell off. Then the Breeze so hurried her across the garden that when they reached the flowers she was out of breath with laughing.

“I suppose that old [Illustration: Spider] is jealous because her children will not be so pretty as my baby [Illustration: Butterflies]” she said.

LADY GRAY AND THE NUTS

One summer Robert and his father and mother lived in a little [Illustration: House] in the woods.

They saw a [Illustration: Squirrel] running about in the [Illustration: Trees].

Robert put some [Illustration: Nuts] on the ground, and hid behind a [Illustration: Tree]. Soon the [Illustration: Squirrel] came and carried them away.

The next day he put the [Illustration: Nuts] nearer the [Illustration: House]. The [Illustration: Squirrel] came again and carried them away.

So it went on for some time. Each day Robert put the [Illustration: Nuts] nearer the [Illustration: House].

They named the [Illustration: Squirrel] Lady Gray.

One day Robert’s mother sat down on a [Illustration: Chair] in the porch. She put some [Illustration: Nuts] on the floor and kept very still.

After a while Lady Gray came up on the porch. She looked at Robert’s mother, then she took a [Illustration: Nut] and ran off as fast as she could.

By-and-by Lady Gray became so gentle that she would hunt for [Illustration: Nuts] in their pockets.

One morning father put a [Illustration: Nut] on his shoulder. Lady Gray jumped on father’s shoulder and ate the [Illustration: Nut]. How they all laughed!

CUNNING NANCY AND HER KITTENS

Three little [Illustration: Kittens] were born in a [Illustration: House] where there were two lively [Illustration: Children] The [Illustration: Kittens] were at once named Tom, Dick, and Harry.

As soon as they were big enough to handle, the [Illustration: Children] began to carry them round, indoors and out. Nancy, the mamma [Illustration: Cat], did not like her [Illustration: Kittens] to be handled so much, for she knew it was not good for them. She mewed, but the children did not notice her distress.

Dick, a lovely grey, seemed to be her pet. She took the best care of him, and seemed most worried when the children picked him up.

One day little Dick could not be found. The [Illustration: Children] hunted for him, but in vain. They noticed that Nancy did not seem anxious, nor did she go looking for her lost [Illustration: Kitten].

They did not notice, however, that she would often go up the [Illustration: Stairs], and stay away awhile from Tom and Harry.

When washing day came, they found out all about it. In a low, dark [Illustration: Cupboard] upstairs, where the soiled clothes were kept, Nancy and Dick were found. Dick was snugly wrapped in the clothes, and purred contentedly. Mamma Nancy lay beside him. She had taken her favorite [Illustration: Kitten] and hidden him, so that the children should not play with him.

THE GOOD LITTLE STARS

Once upon a time a great many little [Illustration: Stars] lived up in the sky.

Their father was the [Illustration: Sun], and their mother was the [Illustration: Moon].

Usually these [Illustration: Stars] were good little [Illustration: Children]. They liked to help brighten the sky and so make the [Illustration: Earth] brighter.

But one night when their mother called to them to come and light up the sky, they came very slowly. They looked very cross. They did not shine when she told them to do so.

Mother [Illustration: Moon] felt sad. She called up from the [Illustration: Earth] some good little [Illustration: Stars]. They were only [Illustration: Flowers] on [Illustration: Earth], but Mother [Illustration: Moon] changed them into [Illustration: Stars] in the sky.

The naughty [Illustration: Stars] felt themselves falling. Faster and faster they fell, until they sank down into the [Illustration: Earth].

They cried and cried until they fell asleep for they were very sorry for what they had done.

In the morning Father [Illustration: Sun] shone out so brightly that everything, even the baby [Illustration: Stars] under the grass, wakened. They began to cry again.

Their father felt sorry for them. He told them they might shine on the [Illustration: Earth].

So now the stars shine in the sky at night, and in the morning, when Father [Illustration: Sun] shines for them, the [Illustration: Flowers] open their eyes and shine in the grass all day.

THE PANIC IN THE FOREST

A timid hare was resting one day in a grove of palm-trees, and a strange thought came into his head.

“What should I do if an earthquake occurred?”

At that moment a gust of wind shook the palm-trees, and some ripe fruit pattered down.

“An earthquake is beginning!” cried the timorous hare. And, starting up, he fled without daring to look behind him. A deer met him as he was racing along.

“What is the matter?” said the deer, catching up with him and running by his side.

“An earthquake is destroying the forest!” the hare gasped out.

The terrible news quickly spread among the hares, deer and rabbits, and they scampered away in wild terror. As they went on, they were joined by elks, buffaloes, elephants, tigers, and rhinoceroses.

“What is the matter?” said each animal in turn, as he joined the fugitives.

“An earthquake is destroying the forest!” they panted, rushing on, and never stopping to see if it were so. At last the line of frightened animals extended across the country for a full mile. All the smaller beasts standing in the path of the army of fugitives were unable to ask any question; they had to race ahead to avoid being trampled down. But as the maddened host was sweeping blindly down to the bank of a great river, which looked like being choked up with dead bodies, a lion came up, and stopped the frightened beasts with a terrible roar.

“What is the matter?” he said to the tigers.

“The buffaloes told us that an earthquake is coming,” said the tigers.

“Who saw it coming?” said the lion.

“We don’t know,” said the tigers. “The elephants know.”

“The rhinoceroses told us,” said the elephants.

“And we heard it from the buffaloes,” said the rhinoceroses, panting for breath.

The buffaloes heard it from the elks; the elks heard it from the deer; and at last it got down to the timid hare.

“Do you mean to tell me,” roared the lion, “that you have all been frightened to death by a timid little hare? Let us go to the grove of palm-trees, and witness this terrible earthquake.”

When they arrived there, the fruit was still pattering to the ground.

“Now, you see,” said the lion, “what comes of following the lead of the most timorous creature on earth. He has made you all more cowardly than he is himself. You ran away without even hearing the noise that frightened him. Henceforward avoid the gossip of the crowd, and trust to your own judgment.”

THE JOURNEY FROM THE CLOUDS TO THE SEA

When the little drop of rain fell, he didn’t know in the least what was going to happen. For a minute or two he felt quite frightened. Then he suddenly found himself rolling down a hill. He had just begun to think it great fun, when he noticed a lot of other drops beside him, all laughing together and all rolling down the hill.

One of them came close to him and touched him, and he found himself growing bigger. Then more and more came up, and presently he saw that he was quite a big fellow. He felt very proud of himself. “I’m getting bigger and bigger every minute,” he said.

Half-way down the hill he looked back, and saw himself stretched out like a line of silver, glittering and shining between the trees and stones and bushes.

“I’m a stream now,” he murmured proudly as he hurried over sand and gravel and clay, “and I’m getting bigger and bigger still.”

Suddenly he found himself falling over a big black rock. Down, down he fell, thirty feet or more. But he was so big and strong now that he didn’t care a bit.

At the bottom of the hill there were a great many rocks and stones right in front of him. “Get out of my way!” he roared. “I’m a river now! Get out of my way!” And he dashed and splashed and flew right over them.

A little farther on he came to a lovely meadow, with beautiful trees hanging down, and birds singing, and great sleepy red cattle standing knee-deep in the long, sweet grass, and the big blue sky shimmering overhead. It was so very, very pretty that he thought he would stay here a while. So he twisted and wound round and round, just to get another look at the trees, and to watch the birds flying from branch and bush.

He laughed merrily to a little boy who was standing on the bank with a fishing-rod in his hand, and hurried on again.

As he turned a corner quickly he saw a great blue plain stretching for miles and miles, with ships and boats and birds dotted here and there on its broad, heaving, shining surface.

“Hello! There is the sea at last!” he cried joyfully, and rushed forward eagerly to meet it. And as he joined the great ocean he shouted out as if he meant that all the world should hear, “Here I am; I’m a sea now!” (See full page illustration on page 68.)

THE SPIDER AND THE FLY

The spider was in a rare temper as she hurried back to the dark corner where she had her home.

“Upon my word,” she muttered, “it is too bad! This is the third time that wretched housemaid has swept my web away. The ignorant creature calls me an insect. I am not an insect. My body is in two parts instead of three; my head is part of my chest; and I have eight legs instead of six.”

The spider sat in her dark corner thinking very hard. Presently a buzzing sound caught her ears, which happened to be placed at the end of her feet. Her six pairs of eyes glistened with anger.

“There’s that old bluebottle again,” she murmured. “His noise makes my head ache. If I make haste and spin another web, perhaps I can catch him before the maid comes with her broom.”

Having made up her mind, the spider began. On the underpart of her body were four tiny tubes, each with about a thousand still tinier holes. From each tube came a thousand delicate threads made of a gummy fluid. The spider’s hind feet combed and twisted them into one fine thread.

The thread gradually increased in length until a draught caught it and carried it to the edge of the window-curtain, to which it clung.

Several other threads were then stretched from point to point.

“Now,” said the spider, “I can go on building my web.”

Line after line appeared as if by magic. The lines crossed and recrossed, and at every point where they touched a tiny drop of sticky fluid held them firmly together.

The spider viewed her work with satisfaction.

Lastly, she ran a more delicate thread round and round in spiral fashion. At the end of an hour the web was complete.

“Now I will test it,” said the spider; and she tried her work here and there, and found it quite good.

Only a short time passed before the big fly buzzed into the elastic strands. The more he struggled, the more he became entangled.

The spider was hungry and very impatient. She darted from her lair and seized the fly with her terrible claws.

At the end of the feelers were tubes from which she poured poison into the body of her prisoner, while with her fore feet she entangled still further the fly’s legs and wings.

In a few moments the bluebottle was quite still. Securely bound up in the sticky strands, bitten and poisoned, it was clear that he would never again buzz about in the sunshine. Then the spider enjoyed a better meal than she had had for a long time.

An hour later the housemaid came along, and, catching sight of the web, she flicked it with her duster.

“That miserable insect has been at its tricks again,” she said.

The spider was just settling down to a quiet nap after her hearty meal. She did not like being disturbed, but it did not matter so much now. She simply smiled to herself. (See articles on Spiders; Flies and Insects in general in Book of the Animal Kingdom.)

THE STORY OF PETER PAN

Every child in the world grows up to be a woman or a man. The only one who doesn’t grow up, and won’t, is Peter Pan. He always stays a little boy, which is very jolly indeed, and he’s friends with all little boys and girls,--as you’ll understand if you read.

The Darlings,--Wendy, John, and Michael,--lived with their father and mother. They were rather poor, but it didn’t matter, they were all so fond of each other. They’d a little maid called ’Liza, and, because they hadn’t the money for a proper nurse, they’d a dog instead, named Nana,--wasn’t it funny?

Peter Pan came every night; the window blew open wide, and in he hopped, without a sound, and hurried to Wendy’s side. And a curious little dancing light came in with Peter as well; this was a fairy lady, and her name was Tinker Bell. Peter was dressed in skeleton leaves; he had pipes on which he played--a delightful person. Wendy was not the least little bit afraid. He talked to her of the Never-Land, where she’d always wanted to go. And he said, “If I only teach you to fly, you can get there now, you know!” So John and Michael were taught to fly, and Wendy too, and they found it’s as easy, when you get used to it, as walking on the ground. And at last, when both their father and mother were out, one Friday night, the Darling children and Peter Pan and Tinker Bell took flight. Away in their little nightgowns they flew, as fast as they could go, till they came to the island, the Never-Land, where all the adventures grow.

Now in this island, I must tell you, were wonderful things to find: unknown birds, and curious beasts, and Redskins, fierce but kind. Fairies were there, and Mermaids, and Wolves,--some wild, some tame; and a Crocodile that had swallowed a clock, and ticked wherever it came. But--hush, let us whisper!--the “Jolly Roger,” a rascally pirate craft, with raking masts, and swelling sails, and guns both fore and aft, was anchored there, and the hideous crew were lying in wait, each man, and the captain, Hook, in particular, to kill little Peter Pan. Hook was not his real name; Peter, some while ago, in open fight, had cut off his hand, so now he’d a hook, you know. And as, with a stern and gloomy air, he paced, on his quarterdeck, he was thinking all the time, “I’d like to wring that Peter’s neck!” And the rest of the horrible band of Pirates were always prowling about, to see if they couldn’t capture Peter, and kill him, without a doubt. They crept along, singing “Yeo-ho-ho”--as stealthily as could be, they, and the bo’sum, who, indeed, was the best of them--one Smee. But the Redskins, with the tomahawks, were on the Pirates’ track, and followed them quite noiselessly,--not a single rustle or crack. For they thought the world of Peter Pan; in fact, they all were rather inclined to kneel at his little feet. And they called him “Great White Father.”

Upon the island there were also some boys--well, counting rightly, there were six: Nibs, Tootles, Curly, and the Twins (no names), and Slightly. And Tootles, by a silly mistake, when he saw the Darlings near, hastily aimed his swiftest arrow, and drew his bow to his ear, and shot poor Wendy. Just at first she was thought to be dead, by her friends. But, finding she wasn’t, they built her a house, in the hope of making amends. They built it right, round her, with branches, leaves, and moss, and lovely make-believe roses clambering quite across. And when it was completed (and it looked remarkably fine), “Oh, Wendy, do be our mother!” they cried, and they hadn’t to ask her twice. “Come in at once, you naughty children!” Wendy delightedly cried; and they all squeezed in, except Peter Pan, who stayed upon guard outside.

There was also a beautiful house under-ground, where elegant mushrooms grew, and a Never-tree also (but every morning they sawed the trunk right through). You entered the house by hollow trees, going up and down quite fast, which was hard at first, but the children did it exceedingly well at last. And here, in the charming underground house, the eight boys slept alone in a great big bed,--for Wendy lived in that dear little house of her own. But every evening she told them stories, and when the stories were done, they’d have a dance in their night-clothes, and a pillow fight,--Oh, such fun! Peter Pan wasn’t always there, because, as you understand, he was busy strolling about the island, or watching with sword in hand. But in the day-time he would come, and take them, not very far, to the blue lagoon, where the weedy rocks and the hundreds of Mermaids are.

And here, one day, both Peter and Wendy received a bit of a shock; for Hook pursued them, and so they climbed on a rock--the Marooners’ Rock. Wendy fainted, and so did Peter. A Mermaid came to see whoever those two little dripping folks on the slippery rock could be. Then Peter perceived the tide was rising, and he tied up Wendy tight to the tail of a kite which was drifting near, and sent her away with the kite. And there he stayed on the rock alone, and he thought he’d be drowned each minute. But the Never-Bird, in her floating nest, came up, and Peter got in it, while the Never-Bird took to a Pirate’s hat, which was luckily close at hand. So Peter went gaily sailing off, and arrived quite safe at land.

Now every night the Redskins were camped above the underground house. And every night the Pirates were creeping, each as still as a mouse (with the terrible Crocodile after them, showing its crunching teeth), while Wendy was cheerfully telling tales to the children down beneath. But, oh dear me! there came a night when that treacherous pirate Hook contrived to surprise the Redskins, and the children; and he took the whole nine children prisoners, exceedingly sad to tell. The only ones who made their escape were Peter and Tinker Bell. And while the unhappy children were roughly carried on board, Peter was off to rescue them, with his trusty dagger and sword. And, just in the nick of time, he arrived. He armed the boys, and they slew, after a most tremendous fight, fifteen of the Pirate crew. And after a thrilling duel, which lasted a very short while, between Hook and Peter, the wicked Hook was thrown to the Crocodile.

So Peter took command of the ship, and they all sailed home, and then, how glad their father and mother were, to have them back again! They all were dressed in the Pirates’ clothes (cut short), and exceedingly grand; and oh, what tales they had to tell of the wonderful Never-Land! Peter, who didn’t like houses at all,--brick ones, and that sort of thing, returned to the Never-Land by himself. But he comes back every spring, and fetches Wendy to help him do spring-cleaning, and Wendy stops and tidies up the little house, which is now in the high tree-tops. As for the boys, they’ve all grown up, so the Pirates’ clothes won’t fit. And as for the great adventures they had, they’ve forgotten them every bit. Only Wendy and Peter Pan can still do just as they please. How happy they are, as they talk up there in the dear little house in the trees!

COUNTING AND NUMBERS

In numbers, as in other primary subjects, a child should be taught and permitted to do things himself. Rousseau said, “What the child does, it easily remembers”; and we shall soon find that time spent in this way is far from being wasted.

Children who have been taught numbers gradually, in this easy, interesting fashion, develop an astonishing aptitude for dealing with figures as they grow older.

COUNTING

Learning to count 1, 2, 3, 4, etc., parrotlike, does very little good. Rather let the child count objects and point out 5 marbles, 6 blocks, etc., in order that you may determine if he knows exactly what 5 or 6 of anything means.

Take a number of blocks or marbles and ask the child to take 3, 5, 7, or any number of them.

Hold up 3, 5, or 6 of them and ask him to tell how many you have. When you are told the number you have, write the figure which tells the number on paper, or the blackboard. Have the child copy the figure, making a large character.

Then reverse the work by writing a figure on paper and asking the child to take the number of blocks the writing asks for.

Spend a few minutes every day in asking him to show you 2 pins, 3 houses, 5 stripes, etc.

Teach the child to count 50 as soon as he has started in his number work at school and later on to 100. Objects should be counted at first and then counters substituted, such as pennies, marbles, blocks, beads, etc.

RECOGNITION OF NUMBERS.--The purpose of counting objects is to give the children a clear idea of number. They should be able to recognize 2, 3, 4 and 5, i.e., be able to tell four objects when they see four, without counting them, also 3, 5, etc. Stories and games with objects should be repeated again and again, until the children can do this easily.

ANALYSIS OF NUMBERS.--When the numbers can be recognized without difficulty, the children should be encouraged to analyze them, i.e., tell what they are made up of, but objects should be put in front of the class to represent the numbers until they can do this readily.

Suppose the number five to be the lesson, each child would take five shells out of its box, and lay them on the desk, thus:--[.....] or [.....] or [.....] etc. The child should always be able to describe what it has done: thus, the first child would say--four shells and one shell are five; the second, three shells and two shells are five, and so on.

Higher Numbers.--The analysis of six, seven, eight and nine may be taught in the same way, each number being taken separately and thoroughly mastered, before proceeding to the next. The children should learn all the different combinations of numbers that make six--three and three, five and one, four and two, three twos, etc.--but always with the objects, and when they have seen the number analyzed by the Teacher, they should do it for themselves with shells, bricks or other objects.

Number Ten.--This is the most important number of all, and it should be thoroughly well taught. The Teacher should show on the table the different analyses that can be made of ten, and the children should lay these with shells or other objects again and again. It is necessary to learn these perfectly, for however well any or all of the numbers may be learned, they are comparatively useless without ten.

FIGURES.--When the figures are introduced they should invariably be shown with the concrete numbers which each figure represents. They say, “Here are four balls” : : “I will show you a figure that means those four balls, =4=, and I will put the four balls beside it, thus:”--4 : :.

NUMBER ON PAPER OR SLATES.--If the children have learned how to use a pencil, they may transfer the number-pictures made with shells to their slates, using dots for “shells,” thus:--: : :.

Then another “picture” may be made with the shells : : : and this be copied on the paper at some distance from the other. Then another is made and copied, and so on until the child sees on his paper all the combinations of numbers that go to make six. He should be able to read them all out, and because a child remembers what he has done himself, it will be found that numbers taught in this way are seldom forgotten.

As the children become more proficient, the two signs + and = may be taught, + means and, = means are. Then they may put on their slates : + : = : : and use these signs in the analysis of other numbers.

MONEY TAUGHT AS NUMBERS

When the children know numbers up to ten, they might play little “shopping” games with coins. Show them actual coins in teaching money. Lessons on money should be given frequently after the first year of school life.

Begin by teaching the value of the cent and the nickel, then the dime, then the quarter, then the half-dollar, and then the dollar.

Make little problems involving change. Develop the ability to make change rapidly. The child may have some money of his own and he should be taught the comparative values of the coins.

SIMPLE TABLE OF MONEY

10 cents make 1 dime.

2 five-cent pieces make 1 dime.

100 cents make 1 dollar.

A quarter of a dollar = 25 cents.

A half-dollar = 50 cents.

$ means dollars and c means cents.

A 5-cent piece is called a nickel, because it is made of nickel.

A cent piece is made of copper.

The other coins named are made of silver.

(See United States Money for more advanced instruction.)

COMBINATIONS OF NUMBERS

We now come to the method of teaching the combinations in Addition and Subtraction.

We can count books, tables, and houses and say that we have counted so many things but we do not add books, tables, and houses. We add books and books, tables and tables, houses and houses.

We count by ones. When we add three beads and two beads we are counting by ones, for it means that we are adding three ones of beads and two ones of beads, making five beads in all.

From =1= to =9= we use only one figure to tell how many we mean. When we wish to say in writing that we have ten of anything we write a =0= after the =1= and have =10=, ten.

1. Add 1 to every number up to 10; later to 20.

2. Subtract 1 from every number up to 10; later to 20.

3. Add:

2 3 4 5 6 7 8 9 10 +2 +3 +4 +5 +6 +7 +8 +9 +10

Here the addends are equal and easily added. The figures should be placed as above and not 2 + 2, 3 + 3, etc., because the vertical form is the natural one which the child will use all through life. It does not look so formal and represents better what he really does with the objects.

4. Add:

1 2 3 4 5 6 7 8 9 +2 +3 +4 +5 +6 +7 +8 +9 +10

Here one addend exceeds the other by 1.

5. Subtract:

2 3 4 5 6 7 8 9 10 -1 -2 -3 -4 -5 -6 -7 -8 -9

Here the minuend is one greater in each case.

6. Teach the parts of 10.

5 2 3 4 9 +5 +8 +7 +6 +1

7. In adding 9 to numbers have the child think of 9 as 10,

thus 9 10 9 10 +6 = +5 and +8 = +7

8. Teach the corresponding subtractions.

9. Add 8 to each number up to 10.

10. Teach the corresponding subtractions.

11. Add 7, 6, and 5 to each number up to 10.

12. Teach the corresponding subtractions.

13. Review and give combinations not taught above.

Objects should be grouped by tens and units, in showing numbers above ten. Ten should be the basis of all our reckoning, and if the children know ten, and the numbers which precede it, they can soon be taught the rest. Little children should not have “sums” given them to do on their slates, for “sums” are made up of abstract figures, and children of tender years cannot grasp the abstract.

NUMBER TO ONE HUNDRED.--When the children are conversant with numbers up to ten, it is very easy to teach them one hundred.

PRIMARY IDEAS OF DIVISION

In teaching the two ideas of division--division by measurement (division proper) and the fractional idea of division (partition)--proceed very slowly and see that each step is thoroughly understood.

The following suggestions may be useful:--

DIVISION BY MEASUREMENT

Use blocks or any other counters in illustrating the process.

EXAMPLE:

4 | 12 --+

The teacher should ask the child, “How would you count this story?”

Facts Given by Child

12 = whole number of blocks. 4 = number in each part.

We want to know the number of parts.

We place the blocks so, 4 in each part:--

□□□□ □□□□ □□□□

There are 3 parts.

DIVISION BY PARTITION

Make use of blocks or substitutes to show the process here.

EXAMPLE: 1/4 of 12 = 3.

The teacher should ask the child, “How would you count this story?”

Facts Given by Child

12 = whole number of blocks. 4 = number of parts.

We want to know the number in each part.

We place the blocks so, as we know there are 4 parts:--

□ □ □ □

We have put one in each part.

Now we will put one in each part until the 12 blocks are gone:--

□□□ □□□ □□□ □□□

There are 3 in each part.

NUMBERS IN MULTIPLICATION

Example:

3 × 4 = --

Facts Given by Child

3 × 4 means 3 4’s.

I count my blocks by fours--I take 1 four, another, another.

I find that 3 4’s are 12.

3 × 4 = 12.

To the Teacher:

Now the child is ready to give a number story about 3 × 4.

PRIMARY MEASURES FOR CHILDREN

The child has been taught to count. Now while he is telling you how many objects he is dealing with, teach him to tell how much he is dealing with.

In other words, have the child measure and compare as well as count.

Ideas of larger and smaller, longer and shorter, and the like, should be made important. The need at the outset, is to learn, in a simple way, the basis of all arithmetic--the comparison of quantity,--in as many of its forms as possible.

MEASURES OF LENGTH

Teach the child to estimate distances and then to verify every estimate by actual measurement.

Teach half inches as well as inches.

Long measure is used to measure length.

12 inches make 1 foot. 3 feet make 1 yard. in. means inch or inches. ft. means foot or feet.

For the Child to Do:

1. Cut a strip of paper 12 inches long and 1 inch wide.

2. Mark the inches on it.

3. How many inches long is it?

4. What do you call a measure 12 inches long?

5. Draw a line 2 inches long, as near as you can, without using a ruler.

6. Measure it with a ruler. Did you guess nearly right? Try again.

7. Measure this page. How long is it? How wide?

8. Draw a line on the ground 1 yard long.

9. 1/2 of a foot is how many inches?

10. 1 yard is how many inches? What is measured by the yard?

11. Ask your mother how many yards of cloth she needs for a dress.

12. What is measured by the foot?

13. How tall are you?

TELLING THE TIME

First--Teach him to tell the hour hand from the minute hand.

Next--Teach him when he first looks at the dial, to find the hour hand and then notice which Roman Numeral it is nearest. This will tell about what time it is.

Then--Find the minute hand. The minute hand will tell exactly what time it is.

TO ILLUSTRATE: Take this clock. The hour hand is near the Roman Numeral II., which stands for 2. Tell the child it is somewhere near two o’clock.

The minute hand will tell how near.

It must always point to the XII. before it is exactly the hour. If it is one numeral away from the XII., toward the left, it is 5 minutes of two. If it is two numerals away to the left it is 10 minutes of two, etc. If it is one numeral away to the right, it is 5 minutes after two, etc. Proceed in this way and keep at it.

THE DAY

A new day begins at midnight and lasts until the next midnight.

Midnight is the middle of the night; that is, 12 o’clock at night.

Noon is the middle of the day, that is, 12 o’clock in day time.

One hour after noon is 1 o’clock, 2 hours after is 2 o’clock, etc.

If a person says he was at a certain place at 2 o’clock, he must say forenoon or afternoon, so we will know which half of the day he means. If it was 2 o’clock in the morning he would write 2 A.M., and if 2 o’clock in the afternoon, 2 P.M.

Things for the Child to Do:

1. Name the days of the week and the months of the year.

2. What day of the week does Christmas fall on this year?

3. Is 22 days longer than 3 weeks?

4. Is 5 weeks longer than a month? How much?

5. How many days in 3 weeks?

6. On what day of the week will your next birthday be, etc.

Remember:

The days of the week in their order.

The months of the year in their order.

Procure a calendar for the child to own.

A good way to make him familiar with the use of the days of the week and month, as found on a calendar, is to ask him to look up and tell on what day of the week the next Fourth of July will fall; Christmas; New Year; his birthday.

Have him distinguish between the day of the week and the day of the month.

7 days make 1 week. 30 days make 1 month.

DAYS OF THE WEEK

Sunday Monday Tuesday Wednesday Thursday Friday Saturday

MONTHS OF THE YEAR

January February March April May June July August September October November December

THE CALENDAR

+-------------------------------------------------------+ | 1903 July 1903 | +=======+=======+=======+=======+=======+=======+=======+ |Sun. |Mon. |Tues.|Wed. |Thur.|Fri. |Sat. | +-------+-------+-------+-------+-------+-------+-------+ | First | Full | Last | | | | | | Quar. | Moon | Quar. | 1 | 2 | 3 | 4 | | 1st | 9th | 17th | | | | | | 30th | | | | | | | +-------+-------+-------+-------+-------+-------+-------+ | | | | | | | | | 5 | 6 | 7 | 8 | 9 | 10 | 11 | | | | | | | | | +-------+-------+-------+-------+-------+-------+-------+ | | | | | | | | | 12 | 13 | 14 | 15 | 16 | 17 | 18 | | | | | | | | | +-------+-------+-------+-------+-------+-------+-------+ | | | | | | | | | 19 | 20 | 21 | 22 | 23 | 24 | 25 | | | | | | | | | +-------+-------+-------+-------+-------+-------+-------+ | | | | | | | New | | 26 | 27 | 28 | 29 | 30 | 31 | Moon | | | | | | | | 23d | +-------+-------+-------+-------+-------+-------+-------+

FORM AND COLOR

In many schools a lesson is given on Form and Color at least once a week. The different forms should be kept in a box, in which there should be also squares of cardboard, showing the various colors. This apparatus should, however, be amply extended. Pieces of silk or colored paper should be kept in another box, and colored wools wound on pieces of cardboard show the colors nicely.

THE OBJECT OF THE LESSON.--The object of the lesson is not simply to teach the shape or color of one particular piece of wood, or cardboard, but to enable the child to distinguish the same shape or color whenever it sees an example of it. Thus the child is helped to observe and compare, and its interest in life is strengthened as it learns with joy to find out things for itself.

FORM

The Circle, or round, is the first form to be taught, and it should be illustrated by numerous examples, such as a plate, a round cake, coins, etc.; all these things should be shown to the children.

Then the circle may be compared with the ball, and the children are asked: “What things are round like the ball?” “Orange, apple, etc.” “And what things are round like a circle?” “A penny, a shilling, etc.” “What has the circle that the ball has not?” “The circle has two flat faces, and the ball has only one round face.”

The Square is somewhat familiar to the child, who has noticed the shape of his books, and the table. It has four sides all the same length; this fact may be taught thus:

Take a long stick or ruler. Teacher says: “I will measure the sides of the square. Johnnie shall hold it for me” (measure the top edge, and cut off a piece of stick just the length). Show it to the children, and say: “This stick is just as long as the top edge of the square. I will give it to Mary to hold. Now we will measure the bottom edge” (again cut the length). “This is the length of it” (holding up the stick).

The right and left sides are measured in the same way, and the child now holds four sticks. Let the children count how many sticks there are, and notice also that all four measure exactly the same, and then they will see that the square has four sides all the same length. Then ask for objects of this shape.

The Oblong is measured in the same way as the square, and the sticks are cut the lengths of its sides. The children then see that the sticks cut to represent the sides of the oblong are not all of the same length, but that two are short, and two longer, so the oblong must have two long sides and two short sides. Let a child point to the two long sides, and another to the short ones.

Then the children are asked to name all the things they can see that are oblong in shape, such as the table, door, window. They may also name objects at home--dresser, piano, bed, and many other things.

The Oval is frequently taught after the circle, but as the difference between square and oblong is more marked than the difference between circle and oval, the former comparison if taken first may help the child to understand the latter.

Take a square and draw a circle on it, then take the oblong and draw an oval shape upon it. Ask the children, “How is this shape different from the round shape on the square?” “It is longer.” “Why?” “Because the oblong is longer.”

Now show the oval with the round or circle. “How is the oval different from the round?” “It is longer.” “What things do you know that are shaped like the oval?” “An egg, a basket, a bathtub, a dish, etc.”

The Sphere, Cylinder, Cube, Cone and Pyramid are solid figures. The cylinder can be explained from the sphere, the cone from the cylinder and the pyramid from the cube.

The pyramid points upward, so, But it is square and flat below: The cone is pointed, too, and round; A sugar loaf like it is found.

The children soon learn the difference between the Cone and Pyramid, and if they are allowed to make all these solid figures in clay they will remember them more easily.

1. The oval shape is like an egg, The circle’s round as all can tell, The sphere is round, just like a ball, The cylinder you know quite well;

2. We roll it gently on the ground, For it is very smooth and round; It has two faces flat, you see, And stands, as well as rolls for me.

3. The cube has six square faces, flat, And corners eight, just think of that! And edges twelve, three fours you know, Which round the faces always go.

The Pentagon, Hexagon, Octagon and other similar forms should be learned by drawing them on checkered slates or paper. These figures introduce the obtuse angle, and before the children learn the shapes, they should understand clearly the difference between the right, acute, and obtuse angles. The hexagon and octagon can be combined so as to make pretty designs which may be used for perforating and embroidery.

The “Forms” may be further impressed on the mind of the child by means of a Story; see the one given after “Color,” at end of this chapter.

COLOR

Color should be taught if possible from objects and pictures. The six colors can be illustrated by fruits, as an orange, a rosy apple, a purple plum, a red cherry. The children’s dresses, their eyes and hair, can all be brought into a lesson on color. In spring and summer flowers make charming illustrations, e.g., different colors seen in roses, and the autumn-tinted leaves can be used likewise.

Then there are colors in pictures, trees, besides colored wools, beads, tablets, etc.

Ask for flowers and fruits of certain colors, e.g., what flower is yellow? What fruit is red?, etc. Also colors of birds and animals, and let the children say what colors look nice together. In summer this may be shown by arranging a number of flowers in a bouquet.

In the flowers themselves colors always harmonize, e.g., forget-me-not is blue, and has a yellow center, because blue and yellow look pretty together.

Spring flowers are mostly yellow, and have pale green leaves, for green and yellow look pretty together.

The red poppy and blue cornflower look pretty among the yellow corn, and there are yellow flowers among the corn also.

Harmony of color may be further illustrated by the dressing of a doll, or a story of a little girl who was taken to the shop by her mamma. The little girl was to have a new dress, cloak, and hood; what colors would her mamma choose?

Secondary Colors.--Teach that red, blue and yellow are the first or primary colors, from which other colors may be made. A child’s box of paints and six small tumblers are required for the following illustration.

Pour a little water into each tumbler, and mix a little red paint in one, a little blue in the next, and a little yellow in the third. These are the primary colors.

Let us see what can be made by mixing two of them together. Take an empty tumbler. Pour in a little blue water and a little yellow. Mix together and the children will see that green is produced. Now take another tumbler and mix blue and red in it; this makes purple.

In another tumbler show that red and yellow make orange. “What beautiful thing have you seen in the sky showing all these colors?” “A Rainbow.”

This is a most interesting lesson, and if the tumblers, etc., are not obtainable, the same experiment may be shown on a piece of white cardboard. Paint the colors in stripes on the cardboard, first the three primary, which should be allowed to stand; then the secondary are produced by rubbing one color over another, e.g., paint over the red with blue, and purple is produced. Over the blue stripe paint a little yellow, and we have green. Over the yellow stripe paint red, and orange is seen.

The primary colors are Red, Yellow, Blue, The Red and Blue mixed will show Purple to you; Mix Yellow and Blue if you wish to make Green, Mix Yellow and Red, then bright Orange is seen.

COLOR STORY

After the forms and colors have been learned, they may be woven into an interesting story, thus:

“A man had a large piece of land to make into a garden; he gave a piece to each of his children, and said they might make small beds of any shape that they liked.

“So Johnnie made a round bed” (draw shape on board, and let children copy on slate), “and Willie had a square bed; Mary said her bed should be oblong, and Nellie made hers oval” (draw each on board, and let the children copy). “Then Gerty wanted hers to be the shape of a semicircle, and Harry said his should be very pretty, for he would make it crescent shape, like the moon.”

When the blackboard is full of shapes the teacher might say: “Now you would like to know what these children had growing in their beds. Johnnie had a pink rose-bush in the middle of his bed.

“Willie sowed red Poppy seeds in rows in his square bed, and Mary had a yellow Iris in the center of hers, with blue Forget-me-nots all round. You remember that blue and yellow look pretty together.”

Whenever possible, pin the flower named on the shape representing the flower bed.

The story should be continued until all the “beds” have flowers in them. The children may be allowed to suggest names of flowers and should be encouraged to choose colors that will harmonize.

STORIES

Stories are the “spice” of childhood. The eager delight with which children beg for a story, and listen while it is told, is in itself a plea for stories, and the routine of lessons should be broken up by setting apart five or ten minutes between them for this pleasant exercise.

USE OF STORIES.--In the first place, story-telling may be made the means of helping the children to acquire familiarity with good English. We all know how limited is the child’s vocabulary, and how difficult it is for a child to express his thoughts. Sometimes when a fact is perfectly well known, the language is wanting in which he can express it.

Second, the child’s sympathy may be cultivated and developed by means of stories. He becomes intensely interested in the subject of the story, and for the time being almost lives the incident over again in his own little life.

A very little child was one day listening to a story about “A lazy boy who missed a school picnic because he was so slow in getting ready. The school children were all on board the steamer, the bell rang, the moorings were loosed, and away went the boat just as the late little boy came running down to the pier.”

The little listener followed the story intently up to this point, and then burst out, “Oh! Auntie, couldn’t they get a little row-boat and take him out to the steamer? I don’t like him to be left behind.”

Stories, then, enlist the sympathy of the child.

Third.--Story-telling strengthens the child’s power of imagination. But, be careful to develop the imagination in a right direction, and not to feed it with anything coarse or cruel.

Fourth.--The stories offer opportunity for inculcating moral truths and sometimes it is possible to teach by stories truths that would be difficult to teach in any other way.

KINDS OF STORIES.--(a) Stories of Real Life--of events which have actually happened, or would be likely to happen. It is in this kind of story that moral truths can be illustrated most frequently.

(b) Fairy Tales.--Some people object to fairy tales, but innocent fairy tales feed the imagination, and often point a moral. Stories of horror and cruelty should never be recounted. Children soon learn to take delight in this class of story, and as a consequence, their moral tone deteriorates. Such stories as “Bluebeard” have this effect, but “Cinderella,” “Sleeping Beauty,” and many others, show that right is victorious in the end, and cannot have any bad effect on the children.

(c) Stories of Nature.--Flowers, rocks, trees, and other objects in nature may be made the subject of pleasant stories, interesting as a fairy tale, and many important truths may be taught in this way. A story of the kind is given as an example.

(d) Stories for Very Little Ones.--These should be exceedingly simple. A dog, a kitten, a bird, anything that comes into the life of a little child, he is delighted to hear about. Many such stories are given in the chapters on Numbers and Reading, and others will suggest themselves to the teacher. They should all be told in baby language, i.e., in language that the child can comprehend. Pictures often suggest a story, which is all the more interesting for being thus illustrated.

The children should sometimes be encouraged to tell what they can remember of the story. In this way they learn to express themselves.

THE STORY-TELLER. (a) We have said before that the language should be simple and easy to understand.

(b) The voice should be modulated, and the story-telling is much more effective when gesticulations are used. The flying of birds, the rustling of leaves, etc., should be accompanied by hand movements on the part of the Teacher.

(c) The story-teller should be in sympathy with the subject of the story, and also with the listeners, otherwise the interest will be lost.

(d) Just as pictures add interest to a story, so do illustrations on the blackboard and these should be frequently given. Sometimes the children may be allowed to draw for themselves objects which have been mentioned in the story.

THE AFTER-EFFECT OF STORIES.--It is well to remember that the child’s taste for reading is largely influenced by the class of stories told to him in early life, and in these days of plentiful, cheap literature, how important it is that the youthful mind should be trained to appreciate that which is good.

If a child has learned to gloat over horrible stories, he will gratify this morbid taste by reading ghastly tales as he grows older, and if, on the other hand, he has learned to love stories that are simple and pure, he will choose reading that is good and elevating.

INDEX

The intelligent use of an index requires careful thought and practice upon the part of the reader or consulter. Many books are over-indexed, and trifling allusions, or even words, made to swell the index. It is obvious, therefore, that a book of moderate compass should use only sufficient space to reveal the important general subjects treated. Besides the general index, the following self-indexing dictionaries and departments should be consulted:

PAGE Scientific Terms Used in Astronomy 37 Dictionary of Important Mineral Products 103 Scientific Terms Used in the Earth Sciences 117 Dictionary of Historical Race Groups 278 Tables of States and Territories 588 Table of State and Territorial Government 650 Colonial Divisions of the World 690 Great American and Foreign Battles 700 Right and Wrong Use of Words 718 Abbreviations, Contractions and Degrees 725 Words and Phrases from Modern Foreign Languages 742-754 Words and Phrases from Classic Languages 755 Pronouncing Dictionary of Literary Allusions 782 Pronouncing Dictionary of Mythology 821

=A= PAGE Abbreviations 725-731 Abu-Simbel 342, 349 Abydos 349 Accent, Marks of 713 Of Words 713 Accounts, Laws Concerning 875 Achæan League 382 Acropolis, of Athens 378 Adjutant Bird 216 Africa, Countries of 443 Lakes of 80 Mountains of 76 Age of Pericles 377 Agra, Description of City 687 Taj Mahal 687 Air, Currents of 92 Alamo, The 617, 618 Alaric, in Athens 384 Albanians 278 Albatross 218 Alder 160 Alewife 225 Alexander the Great: Conquest of Egypt 347 Empire of 380 His Death and Successors 381 Invades Northern India 381 Invades Persia 380 Second Invasion of Persia 381 Settles in Babylon 381 Syrian and Egyptian Campaigns 380 Alexander II., Russia 546-547 Alexandria 349 Schools of 347 Alfalfa 124 Allegory 733 Alligators 221 Alliteration 734 Allusions, Literary 782 et seq. Almond 136 Alpaca 245-246 Alphabet, Formed by Phœnicians 368 Alps, Outlying Spurs 445 Alsace-Lorraine 504 Altdorf 570 Alum 103 Aluminum 103 Amber 108 American Literature: Colonial Period 775 First National Period 776-777 Second National Period 777-778 Summary of 778 American Revolution: Campaigns and Battles 636 Commanders of Armies 636 Forces Engaged 636 Amœba 244 Amphibole 104 Anemones, Sea 243 Anglo-Saxon Kings of England 472 Animalcules 244 Animal Kingdom: Classification by Groups 191 Scientific Classification of 189, 190, 191 Why and How Animals are Classified 189 Animal Life: In Cold Zones 122 In Temperate Zones 121 Animals: Amphibious 223 Animalcules 244 Ant-bear 204 Ant-eater 204 Antelope 199 Ants 238-239 Armadillo 204 Bees 238-240 Birds 208 Bison 200 Buffalo 200 Butterflies and Moths 236 Chamois 200 Ciliates 244 Coral-polyps 243 Deer 200 Domesticated 245 Elephant 203 Fishes 225 Flagellates 244 Fleas 240 Flies 240 Flying 205 Frog 223-224 Gayal 201 Gazelle 201 Giraffe 201 Gnats 240 Gnawing, or Rodents 198 Gnu 201 Hippopotamus 203 Hoofed 199 Ibex 202 Jelly-fish 243 Joint-limbed 230 Kangaroo 204 Koala 204 Leeches 242-243 Lemmings 199 Mammals 191 Map Showing Distribution of Animal Life 188 Markhor 202 Marmot 199 Mice 199 Molluscs 229 Monkey Tribe 191 Mosquitoes 240 Musk-Ox 202 Newts 224 Okapi 202 Opossum 205 Original Home of 122 Pachyderms 203 Pangolin 204 Porcupine 199 Pouched 204 Prairie Dog 199 Rabbit 199 Rats 199 Ray Animalcules 244 Reptiles 220 Results of Domestication 246 Rhinoceros 203 Salamander 224 Sambur 202 Sea Anemones 243 Sea Cucumbers 242 Sea Lilies 242 Sea Lion 246 Sea-Urchins 241-242 Seals 205 Simplest Forms of 244 Sloth 204 Sponges, Group of 243 Squirrel 199 Starfishes 241 Tahr 202 Tapir 204 That Interest Me at the Zoo 193 Toad 224 Toothless 204 Tropical 121 Vicuna 202 Walrus 205 Wasps 238-240 Whales 207 Where First Domesticated 245 Wild Goats 202 Wild Pig 204 Worms 242 Zebra 203 Animals, Domesticated: Alpaca 246 Ass 246 Camel 246 Canary 257 Carp 256 Cat 247-248 Cattle 248 Chickens 257 Dog 251-252 Domesticated Insects 261 Duck 258 Elephant 252 Gayal 252 Goat 252 Goldfish 256 Guinea-pig 252 Horse 252-253 Llama 254 Pig 255 Rabbits 254 Reindeer 254 Sheep 254 Swine 255-256 Yak 245 Zebu 256 Animals, Flying 205 Fox 206 Frog 206 Animals of Prey: Badger 194 Brown Bear 194 Caracal 194 Coyote 198 Fox 194 Hedgehog 195 Hyena 195 Ichneumon 195 Jackal 195 Jaguar 195 Leopard 195 Lion 195 Lynx 196 Martin 196 Mink 196 Mole 196 Mongoose 197 Ocelot 197 Otter 197 Polar Bear 194 Puma, or Cougar 197 Raccoon 197 Sable 197 Shrew 197 Tiger 197 Wolf 197 Annotto 166 Antarctic Ocean 85 Ant-bear 204 Anteater 204 Antelope 199 Antimony 108 Antiochus the Great 382 Antithesis 734 Antony, Mark 398 Apennines, The 511 Apostrophe 733 Apothecaries’ Liquid Measure 860 Apothecaries’ Weight 863 Appian Way 389 Apple 136 Apricot 136 Arabian Nights, Pictures of Arabian Life 407 Arabians 278 Architecture: Assyrian 357 Babylonian 357 Egyptian 349 Persian 371 Arctic Ocean 84 Argentina: Buenos Aires 673 Cities 673 Climate 673 Government 673 History 673 People 673 Physical Features 672 Production and Industry 673 Rivers 672 Argonaut 229 Argument 739 Arithmetic 850 et seq. Decimal Fractions 854 Denominate Numbers 856 Fractions, Common 851 Arlington Cemetery, National Military 626 Armadillo 204 Armenians 278 Arminius, Defeats Legions of Varus 240 Army and Navy of Germany 497 Arnold, Benedict 637 Arsenic 108 Artaxerxes 370 Artichoke 129 Asbestos 113 Ash 160 Asia: China 677 Countries of 443 Famous Mountains of 75-76 India 684 Japan 687 Lakes of 77 Asparagus 128 Aspen, or Trembling Poplar 160 Asphaltum 108 Ass 246 Assiout, Dam and Barrage at 345 Assuan 350 Irrigation Dam at 345 Assyria 353 Cities 355 Civilization of 357 Dynasties of 355-356 Empire of 355 Extent of Empire 356 Fall of Empire 356 History of 355 Inscriptions 355 Nineveh 355 Period of Greatest Splendor 356 Reign of Sargon 356 Religion 357 Assyrian Empire (Map) 298 Assyrians 278-297 Asterisk 733 Asterism 733 Astronomy 12 et seq. Scientific Terms Used in 37 Athens 555 Acropolis 378 Alaric in 384 Downfall of 379 Early History 375 Under Cimon 377 Under Pericles 377 Under a Pure Democracy 376 Atlanta, Description of 591 Atlantic Ocean 84 Atmosphere: Composition of 89 Forms of Vapor 94 Height of 89 How Weighed and Measured 89 Winds and Currents 92 Atmospheric Vapor 94 Atoms, Radioactive 848 Augustus Cæsar 399 Augustus, Death of 401 Aurora-Borealis 101-102 Austria: Historical Outlines 419 et seq. Salzburg 532 Salzkammergut 533 Austro-Hungary 527 Austria-Hungary: Austria and the French Revolution 535 Austro-Prussian War 536 Budapest 529 Cities and Towns 529 Climate and Landscape 528 Congress of Vienna, Period of Metternich 535 Conquest of Hungary 536 Division of Empire 534 Ferdinand II. and Thirty Years’ War 534 Francis Joseph, Emperor 535-536 Hapsburg Power through Marriage 534 Hapsburg-Lorraine Line of Rulers 535 History of 534 Historical Outlines 435 et seq. Industries and National Resources 528 Lakes of 528 Leopold I. and the War of the Spanish Succession 535 Location and Extent 527 Loss of Italian Possessions 536 Peoples and Races 528 Period of Reforms 536 Prague 531 Racial Difficulties Bearing upon the European War 536-537 Religion and Education 528 Revolution of 1848 535 Rivers and Lakes 527-528 Sovereigns of 537 Struggle between Austria and Prussia 536 Surface Features 527 Under Charles V. of Germany 534 Union of Austria and Hungary 536 Vienna 529 War of the Austrian Succession 535 Austro-Prussian War 697 Austro-Swiss War 695 Avoirdupois Weight 860 Ayr 464

=B=

Babel, Tower of 354 Baboon 192 Babylon, City of 354 Taken by Alexander the Great 381 Under Belshazzar 357 Babylonia 353 Architecture 357 Art of 357 Civilization of 353, 357 Conquered by Assyria 354 Famous Cities of 353 Historical Outlines 312 et seq. History of 354 Land of 353 Later Empire 356 Period of Hammurabi 354 Reign of Nebuchadnezzar 356 Religion 357 Babylonian Captivity of the Jews 360 Babylonians 278, 297 Baden, Cities of 504 Badger 194 Bagdad, Capital of Eastern Saracens 407 Railroad 577 Balkans, The, Historical Outlines 437 et seq. Balkan War 698 Baltic Sea 86 Baltimore: Buildings, Divisions, Institutions, Parks, Streets, etc. 591 Description of 591 Johns Hopkins University 591 Bamboo 166 Banana 142 Banana Plant 143 Banting 246 Barbarian Invasions of Roman Empire 694 Barbizon 486 Barium 108 Barley 124 Barnacle 231 Basques 280 Bass 225-226 Bats 205 Battles: American Civil War 634, 644 American Revolution 636 Mexican War 641 War of 1812 638 Great, Historical Outlines 312 et seq. Great American and Foreign 700-710 Contesting Nations or Parties 700-710 Name, Location and Date 700-710 Results 700-710 Bauxite 103 Bavaria, Cities of 503 Beans 128 Bear, Brown 194 Beaver 198 Beech 160 Bees: Bumble 240 Honey 238-240, 261 How the Honey-comb is Made 262 Organization of Hive 261 Structure of 262 What Swarming Means 262 Where the Honey Comes from 262 Wonderful Mouth and Legs of 262 Workers and Drones 261, 262 Beetles: Bombardier 232 Cantharis 232 Colorado 234 Stag 234 Water 234 Begonia 148 Belgium 548 Cities 549 Climate and Landscape 548 Government 549 History of 550 People 548 Products and Industries 549 Religion and Education 549 Rivers 548 Surface 548 Belisarius, Conquests of 404 Belshazzar, Reign of 357 Benares 686 Berbers 280 Berkeley, California 620 Berlin 499 Bourse or Exchange 501 Business Quarter 499 Cathedral 502 Culture and Education 501 Dramatic Theater 500 German Cathedral 500 Industries of 501 Opera Platz 500 Panorama of 498 Parliament Buildings 505 Royal Library 500 Royal Museum 500 St. Hedwig’s Church 501 Suburbs of 501 Tempelhofn Feld 500 Unter den Linden 499 Berne 571 Cathedral 571 Clock Tower 572 Betel-nut 166 Bethlehem 364 Market Place in 365 Big Trees, California 585 Bingen 452 Biography, Historical Outlines 312 et seq. Styles of Composition 738 Birch 160 Birds: Adjutant 216 Albatross 218 Bittern 216 Blackbird 212 Bobolink 213 Bobwhite 219 Canary 213 Cassowary 219 Catbird 213 Chickadee 213 Chicken 219 Climbing 211 Condor 209 Crane 217 Crossbills 213 Cuckoo 211-212 Eagle 209 Egrets 208 Emu 219 Falcon 209 Finch 213 Flamingo 218 Game 219 Grebes 218 Grouse 219-220 Grosbeaks 214 Guinea 220 Gulls 218 Hawks 209 Heron 217 Ibis 217 Jays 214 Lark 214 Mockingbird 214 Nightingale 214 Of Paradise 212 Of Prey 209 Orioles 215 Osprey 210 Ostrich 210, 219 Owls 210 Parrots 212 Partridges 220 Peacock 211, 220 Pelican 219 Penguin 219 Pheasants 220 Plovers 217 Ptarmigan 220 Quail 220 Rhea 219 Robin 215 Running 219 Singing 212 Sparrows 215 Stork 217-218 Swallows 215 Swans 219 Swimming 218 Thrasher 216 Thrush 216 Toucan 212 Turkey 220 Vultures 211 Wading 216 Warblers 216 Woodcock 218 Woodpecker 212 Wrens 216 Bismarck, Otto von 508 Bison 200 Bittern 621 Blackbird 212 Black Hellebore 168 Black Mica 104 Bluefish 226 Blue-grass 124 Blue Grotto 87 Bobolink 213 Bobwhite 219 Boer War 470, 698 Bohemia, Historical Outlines 415 et seq. Bombay 686 Books, Famous 782 et seq. Borax 115 Bosphorus, Panorama of 573 Boston 592 Boston Common 593 Bunker Hill Monument 593 Chief Industries of 595 Custom House 592 First Church of Christ, Scientist 592 Notable Buildings and Parks 594-595 Notable Churches 595 Parks and Squares 595 Public Library 593 Roman Catholic Cathedral 592 Simmons College for Women 594 State House 593 Tremont Street 593 Trinity Church 592 Boston College 594 Boston University 594 Botany, Classification of Plants 182-186 Vegetable Kingdom 119-186 Bourbon, House of 494 Bourbon Line 490 Bourbons, Restoration of 494 Brace 733 Brackets 732 Bramaputra 685 Brazil: Cities 675 Climate 674 Government 675 History 675 People 674 Production and Industry 674 Rivers 674 Surface 674 Bread-fruit 138 Bridal Veil Falls 83 Bristle-worms 242 British Empire: Constitution 652 Executive Departments of 654 Government 652-662 Judicial Departments 660 Meaning of 454 Parliament of 656 Sovereigns of 652 British Isles, Mountains of 75 British North America 579 Broadway, New York 609 Viewed at Night 609 Brome-grass 124 Brussels 550 Column of the Congress 551 Palace of Justice 549 Town Hall 550 Brussels Sprouts 130 Bucharest 562 Buckwheat 125 Budapest 529, 532-533 Buenos Aires 673 Buffalo 200 Building Stones 108 Bulgaria 551 Cities 552 Government 551 History 552 People 551 Productions 551 Sofia 351, 552 Bulgarians 280 Bullhead 226 Bunker Hill, Battle of 636 Burr Artichoke 129 Butterfly 235 Butternut 138 Buttonwood 160 Byzantine Empire 404 Conquered by Turks 404 Conquests of Belisarius 404 Historical Outlines 411 et seq. Overrun by Greeks and Persians 404 Reign of Justinian 404

=C=

Cabbage 130 Cacao 138 Fruit or Pods 136 Cactus 173, 174, 175 Cæsar: And Cleopatra 397 Antony’s Oration 298 Assassination of 397 Conspiracy against 397 Dictator of Rome 396 Rivalry with Pompey 396 Struggle with Pompey 396 Triumphal Return to Rome 397 Cairo 350 Calcutta 686 Calendar 866 Perpetual 867 California Darlingtonia 171 Caliphate, in Spain 407 Caliphs 406 Of Bagdad 407 Calomel 114 Cambridge 595 Andover Theological Seminary 595 Educational Institutions 595 Harvard University 595 Historical and Literary Interests 595 Industrial Establishments of 595 University of 466 Washington Elm 595 Cambyses 369 Camel 246 Campaigns: American Civil War 643-644 American Revolution 636 War of 1812 638 Camphor Tree 158 Canaan, Land of 359 Cana, of Galilee 364 Canada: Area and Population 666 Cities 668 Climate 666 Colleges and Universities 667 Government 668 History 669 Lakes and Rivers 666 Parliament Buildings 668 People 667 Physical Features 666 Products and Industries 666 Religion and Education 667 Canary 213, 257 Capacity, Measures of 860 Capet, House of 493 Capetians 488 Capital Letters: Rules for 724-725 Use of 724 Capitals: Of Countries of the World 443 Of States 588-590 Capri, Blue Grotto of 87 Caracal 194 Carlovingians 488-493 Carnation 148 Carp 226-256 Carpeting 858 Carrots 130 Carthage: Character of State and People 390 Defeat of Hannibal at Zama 391 Destroyed by the Romans 391 Founded by Phœnicians 367 Hamilcar in Spain 390 Punic Wars 389 Struggles with Rome 389 Carthaginians 280 Caspian Sea 77 Cassava 143 Cassowary 219 Castle, Windsor 464-466 Castles, of the Rhine 447 Cat 247-248 Characteristics and Habits 248 Intelligence of 248 Superstitions Regarding 248 Varieties of 247 Catbird 213 Catiline, Conspiracy against Rome 395 Cattelya 148 Cattle: As a Form of Industry 250 Economic Value of the Cow 251 Experiment in Values of 250 General Types of 248 Representative Breeds 248 Caucasus 446 Cauliflower 130 Caxton, Influence on English Literature 764 Cedar 160 Celery 130 Celts or Kelts 280 Central Park, New York 611 Century Plant 174 Cephalotus 171 Cereals 123 Chaldeans 281 Chameleons 222 Chamois 200 Champlain, Lake of 76 Charlemagne: Contributions to Civilization 409 Crowned Emperor at Rome 408-409 Emperor of Germany 505 Germanic Empire of 407 Relation to the Church of Rome 408-409 Subdues Saxons and Bavarians 408 Charles the Great (Charlemagne) 407 Charles V., Emperor of Germany 490-507 Charles VII., King of France 489 Charles Martel, Defeats Saracens at Tours 406 Charts: Comparative Classification of Races and Peoples 293 Development of Man 273 Diagram of Solar System 12 Greek and Roman Mythology 846-847 Historical Maps of World 298, 300, 302, 306, 308 Charybdis 87 Chaucer, Place in English Literature 763 Chayote 129 Cheops, King 346 Cherry 138 Chestnut 160 Chicago 596 Building Architecture of 596 Business Thoroughfares 596 Center of Railroad Industry 598 Chief Manufactures of 598 Educational Institutions 598 Famous Union Stockyards 598 Lake Shore Drive, and Boulevards 596 Loop District, or Principal Business Section of the City 596 Nationality of Inhabitants 596 Parks and Special Attractions 597 Public Library 596 Tunnel System 598 University of Chicago 597 Chickadee 213 Chickens 219, 257 Leading Breeds of Poultry 257 Children: Education and Care of 961 Health of 961 School Life of 961 Chile: Cities 676 Climate 676 Government 676 History 677 Physical Features 676 Production and Industry 676 Chimpanzee 192 China: Area and Population 677 Bridges 678 Canals 679 Cities 682 Climate 680 Government 682 Great Chinese Wall 679 Historical Outlines 41 et seq. History 683 Pagodas 680 Peking 682 People, Religion and Education 681 Production and Industry 680 Rock-hewn Temples at Lungmen 681 Seas, Rivers and Canals 678 Surface 677 Chinchilla 198 Chinese 281 Chinese Wall 679 Chinese-Japanese War 698 Christ, Birth of 400 Christian Era, Beginning of 400 Christians 559 Christianity under Constantine 403 Chrome 109 Church: Historical Events 411 et seq. Historical Outlines 411 et seq. Ciliates 244 Cimon, Adorns Athens 377 Cinchona 166 Cincinnati 598-599 As a Center of Music and Art 599 Chief Places of Public Interest 599 Educational Institutions 599 Notable Buildings of 599 Parks and Museums 599 Principal Streets, Shopping and Residential 599 Rivers and Famous Bridges of 598-599 University of Cincinnati 599 Cinnamon 138 Circular Measures 864 Cities: (See under various countries and states, and individually.) Civilization: Assyrian 357 Babylonian 357 Contributions of Charlemagne 409 Egyptian 343-348 Great Periods in 312 et seq. Oriental 299 Saracenic 407 Where It Began 299 Civil War, American: Campaigns and Battles 642-644 Causes and Results 643 Commanders 643 Killed and Wounded 643, 644 Civil War in England 696 Civil Wars of Roman Empire 694 Classic Tales and Stories 820-847 Classic Words and Phrases 755 Clay 103 Cleopatra and Cæsar 397 Ruler of Egypt 347 Suicide of 398 Cleveland 599-600 Bridges and Viaducts 599 Chief Buildings of 599-600 Chief Business Streets 599 Chief Industries 600 Euclid Avenue 599 Parks and Public Squares 599 Public Library of 599 Water Front 599 Climate 89 Affected by Winds and Ocean Currents 99 Atmospheric Vapor 94 Desert Regions 99 Dew 94 Distribution of Temperature 90 Effect of Earth’s Motions 90 Effect of Rainfall 99 Effect of Unequal Days and Nights 92 Equinox 90 Figures Illustrating 91 Glaciers 97 Heat of Sun 90 How Affected by Land and Water 97 Icebergs 97 Influence of Elevations 99 Mists and Fogs 94 Nature’s Wonders of 101 Seasons 91 Snow 94 Supreme Influence of the Sun 97 Climax 734 Clouds 94-95 Colors of 102 Forms of 93-94 Clove 138 Clover 125 Coal 109 Cobalt 109 Coblence (Koblenz) 450 Cocoa Beans, Drying and Roasting of 137 Cocoa-nut 138 Cod 226 Coffee, Production and Treatment of the Berry 139-140 Coffee Tree 138 Colleges and Universities, see individual names. Cologne 448 Colon 731 Colonial History of the United States: Colonial and Indian Wars 628-633 English Explorers 629 Foreign Rulers and Events 628-633 French Explorers 628 Oppression under British Rule 635 Portuguese Explorers 628 Progress and Population 631, 633 Spanish Explorers 628 Colonies of Countries of the World 690 Colonies: Area and Population 690 Governing Country 690 In Africa 690 In Asia 690 In Europe 691 In North America 691 In Oceania 692 In South America 691 Of France 493 Of Germany 504 Tables of 690 Colorado River: Description 582 Grand Cañon 582 Colugo 205 Comma 731 Commerce, Phœnician 368 Commercial Law 870 Como, Lake 76 Comparative Government 652-662 Condor 209 Congress, American Continental 635 Consonants 713 Tables of Sounds 713 Consulate of France 494 Constantine the Great 403 Favors Christianity 403 Makes Byzantium His Capital 403 Constantinople 574 Dolma-Bagtche Palace 576 Egyptian Obelisk 576 Mosque of St. Sophia 574 Palaces and Mosques 575 Panorama of 575 Situation and Description of 574 Yildiz Palace 577 Constellations 24 (See also Stars.) Mythology of 36 Visible Each Month 30 Continents 51-52 Area and Population 442 Average Height of 52 Contractions 725-731 Copenhagen 554 Frederick’s Church 554 Copper 104-109 Coral Islands 58 Coral-polyps 243 Cork Oak 162 Corn 125 Costliest Ears in the World 125 Coronas 101, 102 Correct English 712 Corundum 103, 104 Cotton 166 Cougar 197 Countries: (See also individual names.) (See Book of Nations, 297 et seq.) Area 443 Capitals of 443 Colonies of 690 Comparative History of Nations 312 et seq. Forms of Government 442 Independent Countries of the World 443 Population 443 Salary of Ruler or Head 443 Statistics of 443 Wealth of 443 Coyote 198 Crabs 230, 231 Cranberry 143 Crane 217 Crayfish 231 Crickets 237 Crimean War 469, 597 Crocodiles 221 Crossbills 213 Crusades, Wars of 695 Cryolite 103 Cryptogams 158 Cubic Measure, Applications of 859, 860 Cuckoo 211-212 Cucumber 130 Currant 143 Currents: Air 92 Gulf Stream 88 Ocean 88 Polar 88 Cuttlefish 229 Cyaxares, the Mede 369 Cypress 162 Cyrus the Great, Founds Persian Empire 369 Czars, of Russia 548

=D=

Dacian War 694 Dagger 733 Dahlia 148 Damascus 364 Danish America 579 Danish Kings of England 472, 473 Danish War 697 Danish West Indies 579 Danube, The 453 Chief Towns of 454 Description of 453 Historic Importance 454 Dardanelles, Allied Campaign against 577 Darius the Great 370 Darius III., Last of the Persian Emperors 371 Dark Ages 403 Darnell 168 Dash 732 Date, Date-Palm 138 David 359 Day, Where It Begins 867 Day and Night, How Caused 91 Law of Variation 92 Days, Names of 868 Days and Nights, Table of Unequal 92 Dead Sea 77, 362, 363 Deadly Nightshade 168 Decimal Fractions 854 Deer 200 Degrees 725-731 Delhi, Description of 686 Deltas 71 Democracy, Established in Rome 388 Demosthenes, Inveighs against Philip of Macedon 380 Denmark 553 Cities 554 Climate 553 Copenhagen 554 Government 554 Historical Outlines 411 et seq. History 554 People 553 Production and Industry 553 Surface 553 Denominate numbers 856 Reduction of 856-857 Denver 600 Chief Sources of Wealth 601 Climate 601 Educational Institutions 601 Main Business Streets 600 Notable Buildings of 600 Principal Features of 600 Surrounding Mountains 600 Description, Forms of Written 739 Desert of Gobi 99 Deserts and Desert Regions 99 Deserts, of Egypt 344 Des Moines 600 Des Moines College 600 Drake University 600 Manufacturing and Commercial Importance 600 Detroit 601 Center of Commercial and Industrial Activity 601 Parks 601 Principal Business Streets 601 Prominent Buildings 601 Public Library 601 Dew 94 Diagrams: Earth’s Strata 40 Famous Mountains 72, 73 Famous Rivers 72, 73 Showing Average Height of the Continents 52 Diamond 109-110 Diamonds, Celebrated, of the World 111, 112 Dictionaries: Classic Words and Phrases 755 French Words and Phrases 742 Gems or Precious Stones 109, 110, 111, 112 German Words and Phrases 742 Historical Race Groups 278-292 Italian Words and Phrases 742 Literary Allusions 782 et seq. Minerals 103 Modern Foreign Languages 742 Of Mythology 820-847 Scientific Terms Concerning Animals 263-264 Scientific Terms Used in Astronomy 37 Scientific Terms Used in Botany, 176, 177, 178, 179, 180, 181, 182 Scientific Terms Used in the Earth Sciences 117, 118 Spanish Words and Phrases 742 Didactic Poetry 740 Dog 251-252 Different Breeds of 251 Dogwood 162 Dolphin 207 Domesticated Animals 258-262 Dorian Invasion 373 Dorians 374 Dormouse 198 Douc 192 Draco, Laws of 375 Dragon, Flying 222 Drama: Dramatic Poetry 740 How to Write 738 Dresden 503 The Zwinger 503 Dry Measure 860 Duck 248 Chief Breeds 258

=E=

Eads Bridge 622 Eagle 209 Ear 933 Middle 935 Physiology and Structure 933 Plate of Internal 934 Earth: Animal and Plant Life in Strata of 40 Area and Population by Continents 442 Characteristic Rocks 48, 49 Cross-section Showing Interior 41 Distribution of Plants and Animals 121 Effect of Motions on Climate 90 Electricity of 101 Geological Growth of 48, 49 Heat of 41 Hemispheres and Continents 443 Land Forms 51, 52 Languages of 442 Life Ages of 48, 49 Life upon 121 Minerals of 48, 49, 103 Races and Populations 442 Revolutions of 91 Rotation of 91 Structure and Surface 41 Tropical Life 121 Vegetable Kingdom 119 et seq. Earthquakes 65 Causes and Motions of 65 Notably Destructive Ones of History 66, 67 Earth Sciences, Glossary of Scientific Terms 117, 118 Earthworms 242 Earwigs 237 Eastern or Byzantine Empire 404 Historical Outlines 411 et seq. Ebony 162 Ecbatana 371 Eclipses 34, 35 Edinburgh 462 Editorials 739 Education, of Children 961 Eel 226 Egg-plant 130 Egrets, American 208 Egypt: Ancient Population 344 Architecture 349 Assuan Dam 345 Cheops or Khufu 346 Cities 349 Civilization of 348 Cleopatra 347 Climate 344 Conquered by Alexander 347 Conquered by Persia 347 Deserts of 344 Doctrine of Future Life 349 Embalming 349 Exodus of Israelites 359 Extent of 343 Fall of 398 Government of 348 Greek Rulers of 347 Heliopolis 351 Hieroglyphics 346 Historical Out 312 et seq. History of, Sculptured in Eternal Rocks 342 How We Know Its History 346 Irrigation 345 Israelites in 359 Kings 348 Lakes of 344 Land of 343 Nile 343 Nile Valley 343, 344 Oases of 344 Oldest Civilization in 343 Painting 349 Pawn of Turkey, France and England 348 Priests 348 Psametik 347 Ptolemies 347 Pyramids 342, 350, 351 Pyramid Builders 346 Rameses 347 Religion 348 Roman Province 347 Rosetta Stone 346 Sculpture 349 Shepherd-kings 342 Social Castes 348 Soldiers and Warriors 348 Sphinx 342, 351 Suez Canal 352 Temple at Abu-Simbel 342 Thebes 347, 352 Under Mohammedans 348 Egyptians 281, 297 Ehrenbreitstein 450 Eiffel Tower 483 Elder 144 Electricity, in Nature 101 Elephant 203, 252 Elizabeth, Elizabethan Period in English Literature, 770, 771, 764-765 Elizabethan Period 468 Ellipsis 733 Elm 162 Embalming, Egyptian 349 Emerald 110 Emery 103 Emperors of Rome 401 Emphasis, or Inversion 734 Empire of Charlemagne: Division of 409 Extent of 407 First Union of Germans under One Head 408 Northern Italy United to It 408 Plan of 407 Empire, of France 494 Empire, Second, of France 494 Emu 219 England: (See also British Empire, British Isles and Great Britain.) Government 652-662 Money and Coins 869 Table of Sovereigns 472 et seq. English, How to Speak Correct 712 Spoken 712 English Civil War 696 English, Correct 713 Abbreviations, Contractions and Degrees 725-731 Accent of Words 713 Capital Letters 724 Choice and Use of Words 717 Common Errors in Pronunciation 715 Expression 716 Figures of Speech 733 Forms of Written English 734 Fundamental Rules 712 Grammatical Connections 716 Inflection of Voice 716 Organ of Speech 712 Punctuation 731-733 Rhetoric 733 Right and Wrong Use of Words 718-724 Rules of Pronunciation 714 Rules Relating to Style 717 Vowels 712 Written English 716 English History 466 Anglo-Saxon Period 466 Creation of England and Scotland 466 Norman Conquest 466 Periods of 466 et seq. Roman Period 466 English Lake District 457 English Literature: Anglo-Saxon Period 762, 763, 769 Beginning of English Comedy and Tragedy 765 Chaucer 763 Elizabethan and Puritan Periods 770, 764-765 Elizabethan Prose Writers 765-766 English Period to the Time of Elizabeth 770 Influence of Caxton 764 Norman-French Period 763, 769-770 Pre-Elizabethan Period 770 Puritan Period 766 Restoration to the Rise of the Novel 766-771 Rise of the Novel and Period of Romanticism 767-772 Romanticism and the Early Nineteenth Century 768 Shakespeare 765 Summary of Writers 769 Tennyson and Other Poets 769 Victorian Period to the Present 768-775 English Money 869 English, Written 716 Argument 739 Biography 738 Description 739 Editorials 739 Essay 739 Exposition 739 Fiction and Drama 738 Forms of 734 Forms of Poetry 734, 739 Letter Writing 734 Narration 738 News and the “Story” 738 Poetics 739 Prose 734 Epic Poetry 739 Epigram, 734 Equatorial Currents 88 Equinox, Autumnal 90 Vernal 90 Escurial 566 Essay, The 739 Estuaries 71 Eton College 466 Etruscans 282 Eucalyptus 162 Euphemism 734 Euphrates 353 Region around 299 Europe: Alpine Region 445 Continent of 444 Countries of 443 Danube 453 Famous Mountains of 74, 75 Great Powers of 454 Grouping of Nations 454 Gulfs and Inlets 444 Highlands of France 445 Lake Region of 454 Lakes of 77 Lowlands of 445 Mediterranean and Its Arms 444 Mountains and Highlands 445 Mountains of Italy and Balkans 446 Nations of 454 et seq. Outline and Extent 444 Peninsulas of 444 Pyrenees and Spanish Peninsula 446 Rhine 447 Rivers and Lakes 447 Surface Characteristics 444 Surface of Islands 446 European War of 1914-1917 698-699 Events, Great Historical 312 et seq. Exclamation Point 731 Exemption Laws 875 Exodus of Israelites 359 Explorers: English Explorers of United States 629 French Explorers of United States 628 Portuguese Explorers of United States 628 Spanish Explorers of United States 628 World’s Greatest 310-311 Exposition, Forms of English 739 Expression 716 Inflection of Voice 716 Eye: How Color is Determined 937 How We See 937 Retina 938 Rods and Cones 938 Sense of Sight 938 Structure and Marvels 936

=F=

Fables 820-847 Fairmount Park 615 Falcons 209 Famous Books 782 et seq. Famous Mountains 72, 73, 74, 75, 76 Name and Location of 74, 75, 76 Of Africa 76 Of Asia 75, 76 Of British Isles 75 Of Europe 74 Of North America 74 Of Oceania 75, 76 Of Pacific Islands 75, 76 Of South America 76 Famous Waterfalls of the World 80 Height of 80 Location of 80 Famous Writers 782 et seq. Feldspar 103 Fiction, How to Write 738 Fifth Avenue, New York 611 et seq. Figs 141 Figures of Speech 733 Finch 213 Fir 162 Firefly 232 Fishes, Classification and Description of 225-229 (See also under separate Names) Flagellates 244 Flamingo 218 Flax 167 Fleas 240 Flies 240 Flowering Shrubs, Description of 155, 156 Flowerless Plants 158 Flowers: Best Annual 150, 151 Best Perennials 151, 152, 153, 154 Classifications of 147, 148 Cultivation of 150, 151 Description of Annuals 150, 151 Description of Best Perennials 151, 152, 153, 154 Guide for Selection 150, 151 Wild 157 Flying Animals 205 Bats 205 Colugo 205 Fish 226 Fox 206 Frog 206 Phalanger 205 Squirrel 205 Fog 94 Folklore 820-847 Fontainebleau 486 Fool’s Parsley 168 Forage Plants 123 Forest Trees 160 Fossils 46 Fox 194 Flying 206 Fractions, Common 851 Decimal 854 France: Amiens Cathedral 487 Barbizon 486 Beginning of 409 Bourbon Line 490 Capetians 488 Carlovingians 488, 493 Charles VII. and Joan of Arc 489 Chief Magistrate and His Powers 653 Cities and Towns 478 Climate and Soil 477 Colonies and Dependencies 493 Consulate 491, 494 Divisions of 476 Empire of 494 Empire, Second 491-492, 494 Executive, Departments of 655 Government of 653-662 Fontainebleau 486 Franco-Prussian War 492 Highlands of 445 History of 487 House of Bourbon 494 House of Capet 493 House of Orleans 491, 494 House of Valois 494 House of Valois and the Hundred Years’ War 489 Industrial Centers 486 Industries and Trade 477 Judicial Department 661 Legislative Department of 657 Location and Extent 476 Louis IX. 488 Louis XIV. 490 Merovingians 487, 493 Money and Coins 869, 870 Napoleon and the Directory 491 Naval and Military Centers 486 Paris 478 People 478 Petit Trianon, Versailles 486 Products of Soil 477 Religion and Education 478 Republic, First 494 Republic, Second 494 Republic, Third 492, 494 Restoration 491 Restoration of the Bourbons 494 Revolution 490-491 Revolution of 1848 491 Roman Rule of 487 St. Denis 483 Sovereigns and Presidents 493 Surface and Mountains 477 Teutonic Invaders 487 Under the Romans 487 Versailles 483 Wars of Francis I., and Charles V. of Germany 490 Francis I., King of France 490 Franco-Prussian War 492, 698 Frederik the Great 508 French, Influence on English Literature 763, 769-770 Revolution 696 Words and Phrases 742 (See also France.) Freshwater Lakes: Area of 79, 80 Elevation of 79, 80 Location 79, 80 Frog, Flying 206

=G=

Galago 192 Gallic War 694 Ganges 685 Garden of the Gods 584 Garnet 110 Gauls: Invasion of Italy 693 Of Northern Italian Peninsula 386 Gayal 201, 252 Gazelle 201 Gecko 222 Gems 109 Geography: Distribution of Races 275, 276 Historical 299 et seq. Literary 782 et seq. What It Is 299 Geography and Discovery 299 et seq. Geology, View of the Growth of the Earth 48-49 Geranium 148 German Empire 495 Division of 495 Executive Departments of 655 Government and Constitution of 653-662 Judicial Department of 661 Kaiser and His Powers under the Constitution 653 Legislative Department of 657 German Words and Phrases 742 Germans: First Defeat of Romans 400 (See also Germany, German Empire, Holy Roman Empire.) Empire of Charlemagne 407 Germany: (See also German Empire.) Accession of William II. 509 Army and Navy 497 Baden, Cities of 504 Beginning of 409 Berlin 499 Bismarck’s Domination 508 Cities of Bavaria 503 Charlemagne, King 505 Charles V. 507 Chief Cities 498 Climate of 496 Colonies of 504 Commercial and Colonial Expansion 509 Confederation 508 Contest between Prussia and Austria 508 Defense of 497 Divisions of the Empire 495 Dresden 503 Educative and General Culture 497 Elsass-Lothringen 504 Feudal System 505 Frederick the Great and the Seven Years’ War 508 Government 653-662 Hapsburg Line 507 Henry I. 506 Historical Outlines 410 History of 505 Hohenstaufen Line 506 House of Luxembourg 507 Independence of Austria and Union of Germany 508-509 Internal Communications 496 Interregnum 507 Leipzig 503 Money and Coins 870 Otto the Great 506 People and Language 497 Potsdam 501 Productions and Industries 496 Prussian Cities 502 Reformation 507 Religion of 497 Restoration of German Empire 509 Rise of Prussia to Power 508 Rivers of 495-496 Romans, First Contact with 505 Smaller States, Cities of 504 Struggle with the Papacy 506 Surface Characteristics 495 Thirty Years’ War 507 Under the House of Franconia 506 Württemberg 503 Gethsemane 364 Geysers 67 Of Iceland, and New Zealand 67 Of Yellowstone Region 67 Giant’s Causeway 456 Giraffe 201 Gizeh 350 Glaciers 97 Famous Regions of 97 Gladiatorial War 694 Glow-worms 234 Gloxinia 148 Gnats 240 Gnawing Animals 198 Beaver 198 Chinchilla 198 Dormouse 198 Hare 198 Gnu 201 Goat 252 Wild 202 Goddesses 820-847 Gods 820-847 Gold 112, 104 Golden Gate Park 620 Goldfish 226, 236 Goose 258 Chief Breeds 258 Gooseberry 144 Gorilla 192 Government 549 Of Argentina 673 Of Brazil 675 Of British Empire 652-662 Of Canada 668 Of Carthage 390 Of China 682 Egyptian 348 Forms Adopted by Various Nations 442 France 653-662 Germany 653-662 Greece 555 India 686 Japan 688 Mexico 670 Norway 559 Portugal 561 Roman 389 Roman Provincial 391 Rome under the Empire 399 Roumania 562 Servia 563 Spain 565 Sweden 567 Switzerland 571 Turkey 574 United States 652-662 United States, British Empire, Germany and France Compared 652-662 Gracchi, The 394 Grammar, Errors of 716-717 Grammatical Connections 716 Grampus 207 Grand Cañon 582 Grant’s Tomb, New York City 612, 613 Grape 144 Grape-fruit 141 Graphite 104, 113 Grasses 123 Ornamental Lawn 156 Grasshopper 237 Great Battles, Historical Outlines 312 et seq. Great Britain: Ayr 464 British Lakes 457 Cambridge 466 Chief Cities 458 Climate 458 Commercial and Industrial Centers, England and Wales, 461-462 Edinburgh 462 Educational, Historical and Literary Centers 462 English History 466 English Lake District 457 Geographical Features 455 Government 652-662 Historical Outlines 410 Ireland, Commercial and Industrial 462 Irish Rivers and Lakes 457 Islands and Divisions 455 London 458-459 Melrose, and Memorials of Sir Walter Scott 464 Mountains and Lowlands 455 Mountains of 75 Oxford 463 People of 458 Religions of 458 Rivers 456 Scotch Lakes 457 Scotland, Commercial and Industrial 462 Sovereigns of 472 et seq. Stratford-on-Avon 463 Surface of 455 Thames 456 What It Comprises 454 Windsor 464-466 Windsor Castle 464-466 Great Events of History 312 et seq. Great Lakes 583 Great Men, Historical Outlines 312 et seq. Great Rivers: Area of Drainage 71 Deltas and Estuaries 71 Diagram of 72, 73 Length of 71 Where They Empty 71 Great Salt Lake 77, 583 Grebes 218 Greece 372, 555 (See also Greeks.) Accusation and Death of Socrates 379 Achæan League 382 Age of Pericles 377 Alexander’s Invasion of Persia 380 Ancient Divisions of 372 Athens 375, 555 Battle of Marathon 376 Battle of Salamis 377 Battle of Thermopylæ 377 Cities 355 Dorian Invasion 373 Downfall of Athens 379 Early Greek Colonization 372 Famous Islands of 372 Famous Laws of Lycurgus 374 Gallic Invasion of 382 Government 555 Greatest Period of Orators 380 Greek Colonies 374 Greek Kingdoms in Asia 381 Greek Thought in Asia 381 Hellenes 372 Historical Outlines 433 et seq. History of 373 History of Modern 555 Land of 372 Laws and Reforms of Solon 375 Laws of Draco 375 Legendary History of 373 Macedonian Period 380 Minoan Age, The 373 Mycenean Age 373 Mythology 820-847 Mythology, Chart 846, 847 Olympiads 375 Peloponnesian War 377 People 555 Period of Migration 374 Period of Persian Wars 376 Pre-historic Period 373 Production and Industry 555 Pyrrhus 382 Retreat of 10,000 Greeks 379 Rivers 555 Roman Province 383 Sacred Wars 380 Sparta 374 Surface 555 Under Byzantine Empire 383 Under Foreign Rule until 1832 383 Under Turkish Rule 383 Usurpations of Pisistratus 375 Greek Words and Phrases 755 Greeks 282, 299, 372 (See Also Greece.) Alexander’s Successors 381 Conquest of Egypt 347 Empire of Alexander the Great 380 Great Period of Oratory 380 Greek Culture Carried to Rome 393 Historical Outlines 312 et seq. History of 373 History of Macedonia 382 Ionians and Dorians 374 Macedonian Period 380 Philip of Macedon 379 Retreat of the 10,000 Greeks 370 Rise of Macedonia 379 War with Persians 370 Grosbeaks 214 Grouse 219-220 Guava 167 Guinea 220, 259 Guinea-pig 252 Gulf of Mexico 85 Gulf Stream 88 Gulls 218 Gum 162 Gypsies 282 Gypsum 104

=H=

Haddock 226 Hague, The 557 National Monument of Holland 557 Palace in the Wood 557 Halibut 227 Halos 101, 102 Hamilcar 390 Hammurabi, Great Period of 354 Hannibal, Causes of His Defeat 390 Defeated by Scipio 391 Final Fate of 391 Hero of the Second Punic War 390 Hapsburg, Line of 507 Hare 198 Haroun-al-Raschid, Famous Caliph of Bagdad 407 Harvard University 594-595 Hartford 601-602 Architecture of 601-602 Capital 601-602 Industry of 602 Manufactories and Other Industries 602 Parks and Public Bridges 602 Trinity College 602 Hawks 209 Health 961 Heat of Sun, How Distributed 90 Heavens, Book of 13 et seq. Hebron 364 Hebrews 282, 297, 358 David 359 Division of Monarchy 360 History of 359 Maccabees 360 Monarchy of 359 Period of the Judges 359 Saul 359 Solomon 359 Hedgehog 195 Hedge Plants, Description of 155, 156 Hegira 405 Height of Mountains 72, 73, 74, 75, 76 Heliopolis 351 Hellebore 168 Hellenes 372 Hell Gate 87 Hematite 104 Hemispheres and Continents 443 Hemlock 162 Hemp 167 Henbane 168 Henry I., Emperor of Germany 506 Heptarchic Wars 694 Herb Paris 169 Heron 217 Herring 226 Hickory 162 Hieroglyphics 346 Hindus, or Hindoos 283, 297 Hippopotamus 203 Historical Geography 296-309 Maps 296, 298, 300, 302, 304, 306, 308 Known World, B.C. 3800 to B.C. 450 296, 297, 298, 299 About B.C. 450 301 About B.C. 325 301 About 300 A.D. 301 About 500 A.D. 302-303 About 800 A.D. 302-303 About 1000 A.D. 302-303 About 1300 A.D. 302-303 About 1500 A.D. 304-305 About 1600 A.D. 304-305 About 1700 A.D. 306-307 About 1800 A.D. 306-307 About 1915 A.D. 308-309 Historical Outlines: (See also under names of individual countries.) Austria 419 et seq. Austria-Hungary 435 et seq. Babylonia 312 et seq. Balkans 437 et seq. Belgium 429 et seq. Bohemia 415 et seq. China 411 et seq. Denmark 411 et seq. Eastern or Byzantine Empire 411 et seq. Egypt 312 et seq. Germany 410 et seq. Great Battles 312 et seq. Great Britain 410 et seq. Great Men 312 et seq. Great Periods in Civilization 312 et seq. Great Wars 312 et seq. Greece, Modern 433 et seq. Greeks 312 et seq. Holland 418 et seq. Holy Roman Empire 414 et seq. Hungary 415 et seq. India 411 et seq. Italy 410 et seq. Japan 411 et seq. Norway 411 et seq. Ottoman Empire 419 et seq. Persia 419 et seq. Poland 415 et seq. Portugal 414 et seq. Prussia 427 et seq. Russia 415 et seq. Saracens 411 et seq. Scandinavia 411 et seq. Slavs 411 et seq. Spain 410 et seq. Sweden 411 et seq. Switzerland 415 et seq. United States 422 et seq. History: Comparative Outlines 312 et seq. Great Events 312 et seq. Of Argentina 673 Of Austria-Hungary 534 Of Babylonia 354 Of Belgium 550, 552 Of Brazil 675 Of Canada 669 Of Chile 677 Of Denmark 554 Of Egypt 346 Of England 466 Of France 487 Of Germany 505 Of Greece 373 Of Greece, Modern 555 Of Holland 557 Of India 687 Of Italy 524 Of Japan 689 Of Mexico 671 Of Norway 559 Of Palestine 359 Of Phœnicia 367 Of Poland 560 Of Portugal 561 Of Roumania 563 Of Russia 545-546 Of Servia 564 Of Spain 566 Of Sweden 568 Of Switzerland 572 Of Turkey 576 Of United States 634 et seq. Outlines of Nations 312 et seq. What It Is 299 History of England: Boer War 470 Crimean War 469 Elizabethan Period 498 Final Absorption of India 469 House of Hanover 469 House of Lancaster 467 House of Saxe-Coburg 470 House of Stuart 468 Indian Mutiny 469 Magna Charta 467 Period of Commonwealth 468 Plantagenets 467 Restoration 468 Sovereigns of 472 et seq. Tudors 467 Victorian Period 469 Hohenstaufen Line 506 Holland 556 Cities 557 Climate 556 Historical Outlines 418 et seq. History 557 People 556 Production and Industry 556 Rivers and Canals 556 Surface 556 The Hague 557 Holy Land 358 Bethlehem 364 Geography 361 Jerusalem 363, 364 Nazareth 365 Hoofed Animals 199 Hops 167 Horse 252-253 Breeds of 253 Characteristics of Draft Horses 253 Chief Breeds of Draft Horses 253 Noble Character of 253 Original Home of 252 Saddle and Driving 254 Horse-chestnut 162 House of: Hanover 469, 475 Lancaster 467, 474 Orleans 491 Romanoff 548 Saxe-Coburg 470 Stuart 468, 475 Tudor 474, 475 Valois 489 York 474 Howling Monkey 192 Huckleberry 145 Hudson River, Description of 582 Human Body 925 et seq. Ear 933 Eye 936 How We Are Able to Taste, Smell and Feel 939 Hundred Years’ War 695 Hungary: Budapest 532-533 Historical Outlines 415 et seq. Hurricane 93 Hussite War 695 Hyena 195 Hyperbole 733 Hyphen 732 Hyrcanus, John, Revolt of 361

=I=

Ibex 202 Ibis 217 Icebergs 97 Ichneumon 195 Iguana 222 Iguazu, Cataracts of 82 Independence Hall 614 Index, Sign of 733 India: Absorbed by Great Britain 469 Agra 687 Area and Surface 684 Benares 686 Bombay 686 Calcutta 686 Cities 686 Climate 685 Delhi 686 Government 686 Historical Outlines 411 et seq. History 687 Languages 685 Peoples 685 Production and Industry 685 Religions 686 Rivers 684 Simla 686 Indianapolis 602 Architecture of 602 Education and Industry 602 Noteworthy Parks 602 Indian Ocean 84, 85 Indians 283 Indus 684 Insects: Beetles 232 Straight-winged 236 Interest, Legal Rates of 870 Interrogation Point 731 Ionians 374 Iran, or Ancient Persia 299 Ireland: Coast of 456 Giant’s Causeway 456 Rivers and Lakes 457 Iron 113 Irony 734 Irrigation: Assiout Dam 345 Dam at Assiout 345 Of the Nile 344 Rise of 344 Islands: Coral 58, 59 Famous Italian 511 Map Showing Comparative Size 62 Noted, of Eastern Hemisphere 62 Noted, of Western Hemisphere 62 Of North America 578 Volcanic 58 Islands of the World 58 Israelites 282 (See also Hebrews, Jews.) Captivity of 360 Enter Land of Canaan 359 Exodus under Moses 359 In Egypt 359 Italian Peninsula: Important Early Divisions 385 Mountains and Rivers 385 Italian Words and Phrases 742 Italy 511 (See also Italian.) Agriculture and Stock-raising 513 Apennines 511 Chief Cities 513 Climatic and Landscape Features 512 Conquests of Lombards 404 Conquest of Papal States 525 Difficulties of Consolidation 525-527 Education 513 Florence 519 Genoa 520 Historical Outlines 410 History of 524 Influence of Napoleon 525 Islands and Their Surface 511 Kingdom of 511 Lake Como 512 Lake Garda 512 Lake of Lugano 512 Lake of Maggiore 512 Lakes of 512 Lombards 524 Manufactories of 513 Mediæval 525 Milan 520 Minerals of 513 Mountains and General Configuration 511 Naples 520-521 Palermo 522 People and Language 513 Pompeii, Ruins of 521 Port of the Holy Roman Empire 524 Present Kingdom Established 525 Products and Industries 513 Religion 513 Rise of Papal Power 524 Rivers and Coast Waters 511 Riviera 512-513 Rome 513 Seaports of 524 Sorrento 522 Struggle for Independent Nationality 525 Turin 522 Venice 523

=J=

Jackal 195 Jade 110 Jaffa 367 Jaguar 195 Japan 687 Area and Population 687 Cities 689 Climate 688 Government 688 Historical Outlines 411 et seq. History 689 Lakes and Rivers 688 People 688 Production and Industry 688 Surface 688 Tokio 689 Yokohama 689 Japanese 285 Jasper 110 Jays 214 Jericho 365 Jerusalem 358, 363 Captured by Pompey 361 Destroyed by Titus 361 Historic Features 364 Streets and Quarters of 364 Wall of 364 Way of the Cross 364 Jewish War 694 Jews 282 Joan of Arc 489 Johns Hopkins University 591 Johnson Grass 126 Jordan, River of 77, 362 Juanacatlan, Falls of 82 Judas Tree 162 Judgments 875 Jugurthine War 693 Jungfrau 56 Juniper Tree 164 Justinian, Notable Reign and Service of 404 Wars of 694 Jute 167

=K=

Kale 130 Kaolin 103 Kangaroo 204 Katydid 237 Khufu, King of Egypt 346 Kieff, Russia 545 Kingdoms of Nature, Vegetable Kingdom 119 et seq. Koala 204 Koblenz (Coblence) 450 Koran, The 405

=L=

Ladybug 234 Lake: Champlain 76, 584 Como 76, 512 Erie 583 Garda 512 George 76 Huron 583 Lucerne 76 Lugano 76, 77, 512 Maggiore 76, 512 Merom 362 Michigan 583 Ontario 583 Superior 583 Lakes: Distribution of 77 Famous Italian 512 Famous Salt 77 Fresh-water, of the World 76, 79, 80 In Plains 77 Mountain 76 Of Africa 80 Of Asia 77 Of Egypt 344 Of Europe 77 Of Japan 688 Of North America 77 Of United States 583 Relative Size 78, 79 Salt 76, 78 Salt, Area of 75 Salt, Location of 78 Land Measure 858 Language and Literature 712 et seq. Languages: (See also under Countries.) Ancient 755 French Words and Phrases 742 German Words and Phrases 742 Greek Words and Phrases 755 Italian Words and Phrases 742 Latin Words and Phrases 755 Modern Foreign 742 Number Spoken 442 Of India 685 Principal of World 442 Spanish Words and Phrases 742 Lapis-lazuli 110 Larch 164 Lark 214 Latin Words and Phrases 755 Latins or Romans 287 Lawn Grasses 156, 157 Laws: Commercial 875 Concerning Notes and Accounts 875 Exemption 875 Interest 875 Legal Interest 875 Statutes of Limitation 875 Usury 875 Lead 104, 113 Leaders 733 Leap Year 865 Leeches 242-243 Leipzig 503 Leland Stanford, Jr., University 620 Lemmings 199 Lemon 141 Length, Measures of 857 Lentils 130 Leopard 195 Letter Writing 734 Acceptance 736 Ceremonial Letters and Notes 736 Divisions of a Letter 734 Invitations 736 Official and Titled Salutations 737 Official or Business Letters 735 Personal and Social Letters 735 Style of Letters 735 Writing Materials 736 Lettuce 130 Lick Observatory 620 Licorice 167 Lighting 101 Lily 148 Limes 141 Lime Tree 164 Lincoln, Abraham 642 Assassination of 644 Linden or Lime 164 Lion 195 Liquid Measures 860 Lisbon 561 Literary Allusions 782 et seq. Literature 761 American Literature 775 Books as Liberal Educators 762 Brain of Humanity 761-762 Characters in 782 et seq. English 762 Famous Book 782 et seq. Famous Poems and Dramas 782 et seq. How It Has Created New Worlds and People 761 How It Helps Us Interpret Life 761 Literary Allusions 782 et seq. Literary Geography 782 et seq. Pen Names of Famous Writers 782 et seq. Plots and Scenes 782 et seq. References to 782 et seq. Rise of Roman 393 Soubriquets and Nicknames 782 et seq. Vast Range of 761 Why We Study Literature 761 Lithium 113 Lizards 221 Llama 254 Lobster 231 Locust Tree 164 Locusts 237 Lombards in Italy 404 London 458, 459 Art Galleries and Museums 461 Famous Churches 460 Famous Streets and Bridges 459 General Features 458, 459 Monuments and Public Buildings 460 Parks and Squares 460 Places of Amusement 461 Population of 461 Westminster Abbey 460 Long Measure 856 Longitude and Time 864 Lorelei (Lurlie) 451 Los Angeles 602-603 Buildings of Note 603 Climate 603 Industries of 603 Parks and Public Places of Importance 603 People of 603 Public Library 603 Streets and Business Thoroughfares 602, 603 University of Southern California 603 Louis IX., King of France 488 Louis XIV., King of France 490 Louisville 603 Chief Buildings of Note 603 Educational and Industrial 603 Public Parks 603 Lucerne, Lake 76 Lugano, Lake 76 Lung-Fishes 228-229 Luxemburg, House of 507 Lycurgus, Laws of 374 Lydia 369 Lyric Poetry 740

=M=

Maccabees 360 Macedon: Later History of 382 Rise of 379 Under Philip 379 Macedonian Wars 693 Mackerel 226 Madrid 565 Royal Palace 565 Maelstrom 87 Maggiore, Lake 76 Magi, The 371 Magna Charta 467 Magnesium 113 Magnetite 104 Mahogany 164 Mainz 452 Malays 287 Mammals 191 Mammoth Cave 584 Man: Ape-man of Java 269 Cro-magnon Man 269 Development through the Ages 273 First Migrations of 268 In the Stone Age 270 Neanderthal Man 269 Piltdown Man 269 Prehistoric 267-275 Primeval Home of 268 Man and the Human Family 267 Mango 141 Manhattan Island 607 Maple 164 Maps: Distribution of Animal Life 188 Distribution of Plant Life 120 Panama Canal and Connections 649 Marathon, Battle of 376 Marius and Sulla, Civil War between 394 Markhor 202 Marmoset 192 Marmot 199 Marten 196 Marsh Crow’s Foot 169 Marsian or Social War 693 Martynias 170, 171 Massachusetts Institute of Technology 594-595 Mate or Paraguay Tea 141 Matterhorn 56 Mayence (Mainz) 452 Meadow Saffron 169 Measures--See Weights and Measures. Mecca 405 Medes 297, 368 Cyaxares 369 Origin and Character 369 Media: Founded by Cyaxares 369 Medical Signs and Abbreviations 864 Medina 405 Mediterranean and Its Arms 444 Mediterranean Regions (Map) 298 Mediterranean Sea 85 Medo-Persian Empire 368 Meerschaum 113 Melon 130 Melrose 464 Memphis, Egypt 352 Mercury 113 Merovingians 487, 493 Mesquite 164 Messenian Wars 692 Metaphor 733 Metonymy 734 Metre, In Poetry 740 Metropolitan Museum 612 Mexican War 640, 641 Causes and Results of 641 Commanders 641 Principal Battles 641 Troops Engaged 641 Mexico 669 Cities 671 Climate and Landscape 669 Government 670 Gulf of 85 History 671 Mexico City 671 People 670 Production and Industry 670 Rivers and Lakes 669 Surface 669 Mexico City 671 Cathedral 671 Description of 671 Mica 106, 114 Mice 199 Middle Ages 403 Nature of Period 404 Milky Way 32 Millet 126 Milwaukee 603, 604 Business District 604 Chief Buildings 604 Industries and Manufacturing 604 Public Places of Interest 604 Streets of 604 Minerals: Crystallization of 103 Dictionary of 103 Rare Metals 115 Scale of Hardness 103 Table for Identification of 104, 105, 106, 107 Useful, of the Earth 102 Mink 196 Minneapolis 604 Chief Products 605 Chief Streets--Business and Residential 604 Notable Institutions of 604 University of Minnesota 604 Minoan Age, The 373 Mirage 102 Mistletoe 174 Mists 94 Mithridates, Designs against Rome 394 Mithridatic Wars 693 Mockingbird 214 Modern Languages 742 Mohammed 405 Mohammedanism: Characteristics of 405 Rise of 405 Mohammedans, Conquest of Egypt 348 Mole 196 Molluscs 229 Money: English or Sterling 869 French 869, 870 Of Germany 870 Of United States 869 Mongolians 288 Mongoose 197 Monkey Tribe 191-194 Monk’s-hood 169 Monte Rosa 56 Months, Names of 868 Moon: Effect upon the Tides 86 Phases of 19 Surface of 29 Moonstone 110 Moors 288 Mormon Temple and Tabernacle 617 Moscow 544-545 Burned in 1812 294 Noted Buildings and Monuments 545 Moses, In Egypt 359 Moslems 405 Mosquito 240 Moths 236 Mount Ararat 57 Mount Assiniboine 57 Mount Blanc 56 Mount Elburz 56 Mount Everest 56 Mount Nebo 361 Mount of Olives 364 Mount Popocatepetl 57 Mount Ranier 57 Mount Robson 57 Mount St. Elias 57 Mount Salcantay 57 Mount Sinai 56, 361, 362 Mount Tabor 361 Mount Vernon, Home of George Washington 627 Mount Zion 364 Mountain Lion 197 Mountains: Alpine Region 445 Celebrated Peaks 56, 57 Famous 72, 73 Height of 72, 73, 74, 75, 76 Name and Location of 74, 75, 76 Of British Isles 75 Of Europe 445 Of France 445, 447 Of Great Britain 445 Of Italy 446, 511 Scandinavian 446 The Caucasus 446 Mountains and Plains: Of United States 580 The Urals 446 Mouse Tower 452 Mulberry 141 Mushroom 130 Musk-ox 202 Mycenean Age 373 Mythology: Assyrian Gods 357 Babylonian Gods 357 Charts of 846, 847 Dictionary of 820-847 Egyptian Gods 348 Greek and Roman 820-847 Legendary History of Greece 373 Of Constellations 36 Oriental 820-847 Phœnician Gods 368 Scandinavian 820-847

=N=

Names of Days 868 Of Months 868 Napoleon Bonaparte 491 Napoleon at the Burning of Moscow 294 Napoleonic Wars 697 Narration 738 Narwhal 207 Nashville 605 Educational Center 605 Manufactures 605 Prominent Buildings 605 Vanderbilt University 605 Nasturtium 149 National Military Cemetery (Arlington) 626 Nations of the World 442 et seq. (See also Countries.) Nations: Ancient Extinct 297, 299 Comparative History 312 et seq. Extinct Nations of the Past 295 et seq. Forms of Government 442 (See also under Individual Countries.) Great Historic Periods of 312 et seq. Living Nations of Today 295 et seq. Wealth of 443 Natural Bridge of Virginia 586 Nazareth 365 Nebuchadnezzar, Famous Reign of 356 Negroes 288, 289 Nepenthes 171 Nerves: Of Hearing 934 Of Sight 938 Of Taste, Smell and Touch 939 Netherlands--See Holland 556 Netherlands or Holland, Historical Outlines 418 et seq. War of Liberation 696 New England Conservatory of Music 594 New Haven 605 Description of 605 History of 605, 606 Industries 605 Location and Surroundings 605-606 Parks and Squares 605 Yale University 605-606 New Orleans: Chief Buildings 606 Description of 606 French Quarter 606 History 607 Public Statues 606 Streets and Parks 606 Trade and Industries 606, 607 Newport, R. I.: Chief Attractions 607 Description of 607 History of 607 New York City: Bridges 608 Broadway 608-611 Cathedral of St. John the Divine 612 Central Park 611 City Hall 610 Colleges and Other Institutions 608 et seq. Columbia University 612 Court House 610 Districts and Streets 608 Fifth Avenue 611 et seq. Grant’s Tomb 612, 613 History of 612, 613 Location and Environs 607 Manhattan 607 Metropolitan Museum 612 Parks and Squares 608 Public Architecture 608, 609, 610, 611, 612 Public Library 608 et seq. Public Statues and Fountains 608 et seq. Riverside Drive 612 St. Patrick’s Cathedral 611 Systems of Communication 608 New York Harbor 607 News, How to Write 738 Newts 224 Niagara Falls 80, 81, 82, 585 In Winter 81 Nickel 114 Nightingale 214 Nile, The 343 Annual Overflow 344 Assuan Dam 345 Cataracts of 80 Dam at Assiout 345 Irrigation System of 344 Valley of 343, 344 Ninevah 355 Norman Conquest 466, 594 Norman Kings of England 473 Normans, Period of Norman-French Literature 763, 769, 770 North America: Canada 666 Climate 579 Coast-line 578 Countries of 443 Famous Mountains of 74 Islands of 578 Lakes of 77 Mexico 669 Political Divisions 579 Position and Extent 578 Rivers and Lakes 578 Surface 578 United States 579 North Sea 86 Northern War 696 Northmen, Invasions of 694 Norway 558 Christiania 559 Cities 559 Government of 559 Historical Outlines 411 et seq. History 559 People 558 Production and Industry 558 Rivers 558 Notes, Commercial 870 Novel, Rise of, in English Literature 766 Numa, King of Rome 386 Number Table 870 Nutmeg 141

=O=

Oak 164 Oats 126 Oases, of Egypt 344 Oceania, Famous Mountains 75-76 Ocean: Baltic Sea 86 Color of 86 Currents of 88 Depth of 85 Floor of 85 Gulf of Mexico 85 Inland and Border Waters 85 Mediterranean Sea 85 Oceans of the World 84 Red Sea 85 System of Currents 88 Temperature 86 Tides 86 Waves 88 Ocelot 197 Octopus 229 Odontoglossum 149 Okapi 202 Okra 130 Olive 141 Olympiads 375 Onion 131 Onomatopœia 734 Onyx 110 Opal 110 Opossum 205 Orange 141 Orang-outan 194 Orchard Grass 126 Organs, of Speech 712 Oriental Mythology 820-847 Orioles 215 Orleans, House of 494 Osage Orange 164 Osprey 210 Ostrich 210, 219, 259 Ottawa, Description of City 668 Otter 197 Otto the Great 506 Ottoman Empire--See Turkey 572 Historical Outlines 419 et seq. Ottomans 292 Owls 210 Oxford 463 Oyster 229

=P=

Pachyderms 203 Pacific Islands, Famous Mountains of 75, 76 Pacific Ocean 84 Pagodas, of China 680 Painting, Egyptian 349 Palestine 358 Babylonian Captivity 360 Bethlehem 364 Cana of Galilee 364 Captivity of Israel 360 Conquered by Rome 361 David 359 Division of Hebrew Monarchy 360 Fall of Judah 360 Geography of 361 Hebrew Monarchy 359 Hebron 364 History 359 Jaffa 367 Jericho 365 Jerusalem 363, 364 Judah, or Judea, Subject to Persia 360 Judges 359 Maccabees 360 Mountains 361 Nazareth 365 Philistines 359 Return of Hebrews to Jerusalem 360 Saul 359 Situation and Importance 358 Solomon 359 Towns of 363 Palm Family 165 Palms 142 Palmyra 366 Palo Alto 620 Panama Canal, Map of 649 Panama-Pacific Exposition 619 Pangolin 204 Paper Measure 870 Papering 858 Paragraph, Sign of 733 Parallels 733 Parentheses 732 Paris 478 Arch of Triumph 480 Cathedrals and Churches 481 Center of Parisian Life 479 Eiffel Tower 483 Environs and Fortifications 479 Grand Opera House 482 Hotel des Invalides 482 Industries of 482 Latin Quarter and Its Institutions 482 Madeleine, Church of 479 Palace of Justice 481 Palaces and Public Buildings 481 Panorama of 484-485 Pantheon 481 Seine and Its Bridges 478 Squares and Parks 479 Stairway of Honor, Grand Opera House 483 Streets and Boulevards 479 Theaters and Places of Amusement 482 Trocadero Palace 480 Parrots 212, 259 Parsnip 131 Parthenon 378 Parthia 396 Partridges 220 Patricians and Plebeians 387 Pea 131 Peach 142 Peacock 211, 220, 259 Pear 142 Pearl 110 Pecan 142 Peking: Description of 682 Royal Observatory 682 Pelican 219 Peloponnesian War 377, 692 Penguin 219 Peoples: (See also Races and Peoples.) Of Argentina 673 Of Brazil 674 Of Canada 667 Of Chile 676 Of China 681 Of Denmark 553 Of Holland 556 Of India 685 Of Japan 688 Of Mexico 670 Of Norway 558 Of Poland 559 Of Portugal 561 Of Roumania 512 Of Servia 563 Of Spain 564 Of Sweden 567 Of Switzerland 571 Of Turkey 574 Of United States 293 Pepper Plant 145 Peppers 131 Perch 226 Pericles: Age of 377 His Great Achievements 377 Period, The 731 Perpetual Calendar 867 Persepolis 371 Persia 368 (See also Persians.) Artaxerxes 370 Arts and Sciences of 371 Cambyses 369 Cities of 371 Conquest of Egypt 347 Conquest of Judea 360 Court Life in 371 Darius III 371 Great Reign of Darius 370 Historical Outlines 419 et seq. Location and Extent 368 Magi 371 Palaces and Tombs of 371 Persian Life 371 Religion 371 Retreat of the 10,000 Greeks 370 War with the Greeks 370 Xerxes 370 Persian Empire: (See Persia, Persians.) Founded by Cyrus 369 Persian Wars 376, 692 Persians 289, 297 Origin and Character 369 Relation to the Medes 369 Persimmon 142 Personification 733 Peter the Great 546 Petit Trianon 486 Petra 365 Rock-hewn Temples 366 Temples of 365 Petrograd 541-542 Famous Buildings and Monuments 543-544 Petroleum 114 Petsai 129 Phalanger, Flying 205 Pharsalia, Battle 397 Pheasants 220 Philadelphia 613 City Hall 613 Colleges and Other Institutions 614 Description of 613 Fairmount Park 615 History of 615 Independence Hall 614 Public Statues 613 et seq. Streets and Parks 613 et seq. University of Pennsylvania 615 Philip of Macedon 379 Philippine Weights and Measures 870 Philistines 359 Phillipi, Battle of 398 Phœnicia 367 (See also Phœnicians.) Arts of 368 Civilization of 368 Government 367 Great Cities of 367 History of 367 Sidon 367 Tyre 367 Vast Commerce of 368 Phœnicians 297, 367 (See also Phœnicia.) Found Carthage 367 Origin of Alphabet 368 Religion 368 Physiology 871 Pig (See also Swine.) 255 Pig, Wild 204 Pigeon 259 Pike, Bony 228 Pike’s Peak 56 Pine 164 Pine-apple 145 Pisistratus, Usurpations of 375 Pistacia 145 Pitcher Plants 169, 170, 171 Pittsburgh: Chief Streets and Parks 615 Description of 615 History of 616 Manufactures and Industries 616 Public Buildings and Institutions 615 Plane Tree 165 Planets 13 et seq. Plant Kingdom: Chief Divisions of 122 Commercial Plants 166 Cruel Plants 169 Cryptogams or Flowerless Plants 158 Desirable Vines 154, 155 Fiber Plants 166 Flowering Shrubs 155, 156 Flying Seeds 173 Fruit-bearing Plants and Shrubs 142 Fruit Trees 136 Hedge Plants 155, 156 How Plants Defend Themselves 174 How Plants Protect Their Flowers 173 How Plants Travel 172 Nature’s Aviators and Seed-sowers 172 Parasites 174 Plant that Grows in the Snow 174 Plants that Entrap and Kill Animals 170 Poisonous Plants 168 Some Wonders of 169 Trees of the Forest 160 Uses of Liquid Rubber 174 Wild Flowers 157 Plant Life: (See also Plant Kingdom.) In Cold Zones 122 In Temperate Zones 121 In the Tropics 121 Map Showing Distribution 120 Plantagenet Kings of England 473, 474 Plants and Plant Life 119 et seq. Platinum 114 Plovers 217 Plum 142 Poems and Dramas 782 et seq. Poetics 739 Didactic Verse 740 Dramatic 740 Epic 739 Forms of 734 Lyric 740 Metre 740 Poetic Feet 740 Stanzas 741 Verse 740 Poisonous Plants 168 Poland 559 Cities 560 Historical Outlines 415 et seq. History 560 People 559 Surface 559 Warsaw 560 Polar Bear 194 Pollack 227 Pomegranate 142 Pompeii 521 Pompey 395 Death at Battle of Pharsalia 397 Military Expeditions of 395 Rivalry with Cæsar 396 Struggle with Cæsar 396 Poplar 165 Trembling 160 Porcupine 199 Porgy 226 Porpoise 207 Portugal 560 Cities 561 Government 561 Historical Outlines 414 et seq. History 561 Lisbon 561 People 561 Production and Industry 561 Surface and Climate 560 Potato 131 Potsdam 501 Pouched Animals 204 Powers of Europe 548 Prague 531-532 Prairie Dog 199 Prairie Wolf 198 Prawn 231 Precious Stones 109 Presidents of France 493 Presidents of the United States: (See also under United States Government.) Birth and Parentage 662 Career after Leaving the Presidency 664-665 Death and Place of Burial 665 Education, Profession, Religion and Politics 663 Election to the Presidency 664 Marriage and Children 664 Powers of 652 Sobriquets of 664-665 Term of Office 665 Writings of 664-665 Pronunciation: Common Errors in 715 Rules of 714 Prose Forms of 734 Prussia, Historical Outlines 427 et seq. Psametik 347 Ptarmigan 220 Ptolemies, The 347 Puberty, Problems of 964 Public Lands, of United States 587 Punctuation: Apostrophe 733 Asterisk 733 Asterism 733 Brace 733 Brackets 732 Colon 731 Comma 731 Dagger 733 Dash 732 Ellipsis 733 Exclamation Point 731 Hyphen 732 Index Sign 733 Interrogation Point 731 Leaders 733 Parallels 733 Parentheses 732 Period 731 Section Mark 733 Semicolon 731 Sign of Paragraph 733 Punic War, First 693 Second 693 Third 693 Punic Wars 389 Puritans: Influence on English Literature 766 Period in English Literature 764-765 Pyramid Builders 346 Pyramids 342, 350, 351 Sectional View of 351 Pyrenees 446 Pyrites 106 Pyrrhus, King of Epirus 382 War with Rome 388

=Q=

Quail 220 Quirinal Palace, Rome 516

=R=

Rabbit 199, 254 Raccoon 197 Races and Peoples: Comparative Classification 293 Estimated Population of 293 Geographical Distribution of 275, 276 How Classified 274 Man and the Human Family 267 Physical and Mental Characteristics of 275 Population of the Earth by 442 Represented in United States 293 Types of Womankind 266 Radcliffe College 594 Radioactivity 848 Radish 131 Radium, Atoms of 848 Rainbows 101, 102 Rainfall 99 Rameses, Epoch of 347 Ramie 168 Rape 126 Raphia 168 Rapids 80 Rare Metals 115 Raspberry 147 Rat 199 Rattan 168 Ray 228 Red Sea 85 Redtop 126 Redwood 165 Reichenbach, Falls of 83 Reindeer 254 Religion: (See also under Countries of the World) Assyrian 357 Babylonian 357 Chief Religions of the World 442 Egyptian Doctrine of Future Life 349 Egyptian Gods 348 Historical Events of Church 411 et seq. Mohammedanism 405 Of Egypt 348 Persian 371 Phœnician 368 Religions of India 686 Religious Population of the World 442 The Koran 405 Religious Wars in France 696 Reptiles 220 Alligators 221 Chameleons 222 Crocodiles 221 Flying Dragon 222 Gecko 222 Iguana 222 Lizards 221 Snakes 222 Tortoises 220 Turtles 220 Restoration 491 English Literature under 766-771 Revolution, American 635 Revolution of the Earth 91 Rhea 219 Rhetoric 733 Rhine, The 447 Castles of 447 Description of 447 et seq. Falls at Schaffhausen 81 Panoramic View of 448 et seq. Rhinoceros 203 Rice 126 Richmond, Va. 616 Capitol 616 Description of 616 Historic Buildings 616 Historic Cemeteries 616 History of 616 Public Statues 616 Rivers and Lakes: (See also under Countries, Continents, and individual names.) Deltas of 71 Estuaries of 71 Euphrates 353 Great, of World 71 Heads of 72, 73 Jordan 77 Nile 343 Of Argentina 672 Of Brazil 674 Of China 678 Of Europe 447 Of Germany 495-496 Of Great Britain 456 Of India 684 Of Italy 511 Of Mexico 669 Of North America 378 Of United States 581 Picture Diagram of 72, 73 Rhine 447 The Danube 453 Tigris 353 Riverside Drive, New York 612 Riviera 512-513 Roads: Appian Way 389 Great Roman 389 Robin 215 Rocks: How Found 44, 45 Why They Contain Animal and Plant Fossils 46 Rodents 198 Roman: (See also Romans and Rome.) Chronology and Facts about Emperors 401, 402 Civil War 693, 694 Forum 400 Government 389 Law 387 Mythology 820-847 Mythology Chart 846, 847 War with Tarentum 693 Romans 287, 299 History of 386 Romanoff, House of 348 Romanticism: Early Nineteenth Century 768 Period in English Literature 767, 771, 772 Rome 513 (See also Roman, Romans.) Ancient Roman Forum 400 Appian Way 518 Aqueducts of 400 Arch of Constantine 515 Arch of Septimius Severus 515 Architecture, Ancient and Modern 515 As a Literary Center under Augustus 400 As a Republic 389 Assassination of Cæsar 397 Battle of Pharsalia 397 Battle of Philippi 398 Cæsar Dictator 396 Capital City of the Empire 399 Capitoline Museum 517 City in the Time of Augustus 399 Coliseum 516 Compared with Athens 400 Conquest of Egypt 347 398 Conquest of the East by Cæsar 397 Conquest of the Greek States 391 Conquest of Italy 388 Conquest of Palestine 361 Conquest of Sardinia, Corsica and Gaul 390 Conspiracy of Catiline 395 Construction of the Great Roman Roads 389 Contributions to the World 403 Crossing of the Rubicon 396 Destruction of Carthage 391 Division of the Roman World 398 Early Inhabitants of Sicily 385 Epoch of the Civil Wars 394 Epoch of the Punic Wars 389 Establishment of Democracy 388 Fall of Western Empire 403 Famous Churches 517-518 Famous Struggles of the Factions 395 First Defeat by the Germans 400 First Great Code of Law 387 First Triumvirate 395 Gracchi 394 Grandeur After Her Foreign Conquests 391 Great Public Works of 393 Growth of Political and Social Corruption 393 History of Romans 386 How Governed under the Empire 399 Influence of Greek Culture 393 King Numa and Other Legendary Kings 386 Marius and Sulla 394 Mediæval 514 Military Expeditions in Asia 391 Modern Features and Districts 514 Mountains and Rivers of Italy 385 Mythical Period 386 New Rome Contrasted with the Old 393 Origin of Provincial Government 391 Palaces and Art Collections 516 Palaces of Emperors 516 Panoramic View from St. Peter’s Cathedral 510 Pantheon 517 Period of Constantine 403 Pompey, Cicero, Crassus, Cæsar and Catiline 395 Punic Wars 391 Quirinal Palace 516 Reduces Greece to a Roman Province 383 Rise of Native Literature 393 Rise of Pompey 395 Rivalry of Cæsar and Pompey 396 Roads, Famous 518 Roman Forum 515 Roman World Succeeded by the Germanic 403 Seven Hills 513 Situation of Italian Peninsula 385 Splendors of a Festal Day 392 Struggle Between Patricians and Plebeians 387 Subjugation of Macedon 391 Summary of Roman Government 389 Table of Emperors 401 Temple of Janus 400 Under Augustus 399 Vatican 516 View of Monument to Victor Emmanuel II. 526 Villa Medici 516 Villa Umberto Primo 516 War with Pyrrhus 388 Rorqual 207 Rose Culture 149 Roses 149 Desirable Varieties of 149 Rosetta Stone 346 Roumania 562 Bucharest 562 Cities 562 Government 562 History 562 People 562 Production and Industry 562 Rivers 562 Surface 562 Rubicon, Crossing of, by Cæsar 396 Ruby 112 Rumania 562 (See Roumania.) Rurik, House of 547 Russia: Agriculture and Forests 540 Alexander II. 546 Burning of Moscow in 1812 294 Cities and Towns 541 Climate of 540 Divisions of 537-539 Duma 547 Early Traditions 545 Education 541 Eighteenth Century 546 Historical Outlines 415 et seq. History of 545-546 House of Romanoff Established 546 House of Rurik 547 Ivan III. Expels the Tartars 546 Kieff, the First Historic Center 545 Lake District of 540 Live Stock and Fisheries 541 Moscow 544-545 Napoleonic Period 546 Petrograd 541-542 Products and Industries 540 Reactionary Reign of Alexander III. 547 Religion of 541 Rise of Nihilism 547 Rivers of 540 Russo-Turkish War 547 Seaboard and Islands 540 Settlements in and about Moscow 545 Sovereigns of 547, 548 Surface Features 539 Tartar Invasion 545 Turkish Wars 546 Under Peter the Great 546 Vladivostok 545 Russian Empire 537 (See also Russia.) Russo-Japanese War 698 Russo-Turkish War 698 Rye 127

=S=

Sable 197 Sacred Wars of Greece 380 Sahara 99 Saint Denis 483 Saint Lawrence River, Description of 582 Saint Louis 621 Eads Bridge 622 History 622 Public Buildings and Monuments 621 Situation and Description 621 et seq. Streets and Parks 621 Trade and Industry 622 Washington University 621, 622 Saint Patrick’s Cathedral 611 Saint Paul, Minn. 622 Chief Buildings and Institutions 622, 623 History of 623 Roman Catholic Cathedral 622 Situation and Description 622 Streets, Parks and Public Monuments 622, 623 Trade and Manufactures 623 Saint Sophia Mosque 574 Salamander 224 Salamis, Battle of 377 Salaries of Rulers or Heads of Countries 443 Salmon 227 Salt 115, 116 Salt Lake City: Location and Description 617 Mormon Tabernacle and Temple 617 Streets, Public Buildings, and Parks 617 Temple Block 617 Trade and Industries 617 Salzburg 532 Salzkammergut 533 Sambur 202 Samnite Wars 693 San Antonio 617 History of 618 Location and Description 617 Spanish Missions 617 The Alamo 617 Sandalwood 165 San Francisco 618 Chief Streets, Buildings and Parks 618 et seq. Chinese Quarter 620 Colleges and Other Institutions 620 Earthquake and Fire in 1906 618 Golden Gate Park 620 History 620 Location and Description 618 Nob Hill 619 Panama-Pacific Exposition 619 Public Statues and Monuments 619 Trade and Industries 620 Santiago 676 Sapphire 112 Saracen Empire 405 (See also Saracens.) Conquests of 406 Division of 406 In Northern Africa 406 Subjugation of Spain 406 Saracenias 171 Saracens 405 (See also Saracen Empire.) Caliphate at Bagdad 407 Capital at Bagdad 407 Contributions to Art and Learning 407 Defeated by Charles Martel 406 Historical Outlines 411 et seq. Saracen Wars 694 Sardine 227 Sardis 371 Sargon, of Assyria 356 Sassafras 165 Saturn, Rings of 17 Saul 359 Sawfish 228 Saxon Kings of England 473 Scallop 229 Scandinavia, Historical Outlines 411 et seq. Scandinavian Mythology 820-847 Scarabæus 234 Schaffhausen, Falls at 81 Schmalkaldic War 695 Science 850 Arithmetic 850 et seq. Basis of 850 Books of the Earth 40 et seq. Book of the Heavens 12-38 Geology of the Earth 48, 49 Methods of 850 Scientific Terms Concerning Animals 263, 264 Science and Invention 850 Scientific Terms: Botanical Classification of Plants, 182, 183, 184, 185, 186 Concerning Animals 263, 264 Used in Botany 176, 177, 178, 179, 180, 181, 182 Used in Earth Sciences 117 Scipio Africanus 391 Scorpions 231 Scotch Lakes 457 Sea: Aral 77 Caspian 77 Dead 77 Of Galilee 362, 363 Of Tiberias 362 Sea Cucumbers 242 Sea Lilies 242 Sea Lion 206 Seal 205 Seasons: Causes of 91 In Different Latitudes 92 Seattle 620 History of 621 Situation and Description 620 Streets and Buildings 621 Trade and Industry 621 University of Washington 621 Sea Urchins 242 Sea-water: Chemistry of 86 Salt in 86 Section Mark 73 Seleucidæ 381 Semicolon 731 Sepoy Mutiny 697 Sequoia 165 Serbia--(See Servia) 563 Servia 563 Cities 563 Government 563 History 564 People 563 Production and Industry 563 Surface 563 Seven Years’ War 696 Shad 227 Shaddock 141 Shakespeare, Place in English Literature 765 Sharks 228 Sheep 254, 255 Shepherd Kings 346 Shrew 197 Shrimps 231 Shrubs and Plants, Fruit-bearing 142 Sicily, Early Inhabitants of 385 Sidon 367 Silk-worm 262 How It Grows and Feeds 262 Silver 115 Simile 733 Simla 686 Simoon 93 In the Sahara 100 Sirocco 93 Sisal 168 Skates 228 Sky, Colors of 102 Slavery, Rise of Issue in United States 640 Slavs 289, 290 Historical Outlines 441 et seq. Sloth 204 Smelt 227 Snails 229-230 Snakes 222 Snow 94 Height of Snow Line 97 Where Permanent Snow Exists 96 Snow-crystals 94, 96 Socrates, Accusation and Death 379 Sodium 115 Sofia 552 Sorghum 127 Solar System 13 et seq. Sole 227 Solomon 359, 360 Solon, Reforms and Laws of 375 Solstice 90 South America 672 Argentina 672 Brazil 674 Chile 676 Countries of 443 Mountains of 76 Sovereigns of England, Important Facts about 472 et seq. Table of 472 et seq. Sovereigns of France 493 Spain 564 Cities 565 Escurial 566 Government 565 Historical Outlines 410 History 566 Madrid 565 People 564 Production and Industry 564 Pyrenees and Spanish Peninsula 446 Surface 564 Under the Saracens 406 Spanish Words and Phrases 742 Sparrows 215 Sparta 374 Growth and Importance of 376 Supremacy of 379 Training of Citizens 374 Special Senses 933 Speech, Organs of 712 Spelt 127 Sphinx, The 342, 351 Spiders 231 Sponges 243 Spotted Hemlock 169 Springs 69 Spruce 165 Square Measure 857, 858 Practical Applications of 858 Squid 230 Squirrel 199 Flying 205 Standard Time 865 Stanzas 741 Starfish 241-242 Stars: (See also Constellations.) Chart of Southern Constellations 29 Grouping of 24 Magnitude of 24 Milky Way 32 Names of Important 34 Varied Colors of 34 State and Territorial Government 650-651 Governors 650-651 Legislatures 650-651 Members’ Terms 650-651 Persons Excluded from Suffrage 650-651 Previous Residence Required 650-651 Requirements as to Citizenship 650-651 States and Territories of United States 588-590 States: Admission of 588-590 Area and Population 588-590 Capital and Population 588-590 Chief Productions 588-590 Motto and Meaning 588-590 Origin and Meaning of Name 588-590 Original Territory from Which Derived 588-590 Popular Name of 650-651 Where, When and by Whom Settled 588-590 Staubbach, Falls of 83 Statutes of Limitation 875 Stockholm 568 Panorama of 568 Royal Theater 569 Stoke Pogis 466 Stork 217-218 Storms 93 Stratford-on-Avon 463-464 View of 465 Sturgeon 228 Suez 352 Suez Canal 352 Sugar-cane 127 Sulphur 115 Summer Solstice 90 Sun: Distribution of Heat 90 How It Sends out Its Rays 98 Life-giver of the Earth 98 Supreme Influence of 97 Sun-spots, Explanation of 17 Surveyors’ Measure 857, 858 Susa 371 Swallows 215 Swans 219, 260 Sweden 567 Cities 567 Government of 567 Historical Outlines 401 et seq. History 568 People 567 Production and Industry 567 Stockholm 568 Surface 567 Upsala 569 Swine 255, 256 Switzerland 570 Altdorf 570 Berne 571 Cities 571 Climate and Scenery 570 Government 571 Historical Outlines 415 et seq. History of 572 People 571 Production and Industry 571 Rivers and Lakes 570 Surface 570 Sword-fish 227 Sycamore 165 Synecdoche 734 Syria 381 Antiochus the Great 382 Damascus 364 Palmyra 366 Tadmor 366 The Seleucidæ 381 Syrian Monarchy 381

=T=

Tables: American Literature 778-779 Campaigns and Battles of the American Revolution 636 English Literature 769-770 Identification of Minerals 104, 105, 106, 107 Planting for Garden Vegetables 132, 133, 134, 135, 136 Sounds of Consonants 713 States and Territories 588-590 World’s Greatest Explorers 310-311 Tadmor 366 Tahr 202 Taj Mahal 687 Talc 106 Tapir 204 Tariff, Rise of Policy 639 Tea 147 Tea Plant, Its Cultivation 146 Tell, William, Statue of 570 Temperate Zones: Animal Life of 121 Plant Life of 121 Temperature of Oceans 86 (See also under Climate and Temperature.) Temples: Of Janus 40 Of Petra 365, 366 Of Philæ 345 Tennyson, Place in English Literature 769 Terrapin 221 Teutons 291 Texas Land Measure 858 Thames, The 456 Description of 456, 457 Thebes 352 Thebes, Greece: Destruction of 380 Rise of 379 Thermopylæ, Battle of 377 Thirty Years’ War 696 Thorn Apple 169 Thrasher 216 Thrush 216 Tides 86 Effect of Moon on 86 Height of 87 Tiger 197 Tigris River 353 Time: Calendar 866, 867 Measures of 865 On Shipboard 868 Where the Day Begins 867 Timothy 127 Tin 115 Titles, Official, Clerical, Royal and Noble 737-738 Toad 224 Tobacco Plant 168 Tokio 689 Tomato 131 Topaz 112 Tornadoes 93 Tortoises 220 Toucan 212 Tours, Battle of 406 Tower of Babel 354 Model of 355 Trade Winds 93 Treaties, Historical Outlines 411 et seq. Trees of the Forest 160 Trees: Bark, Cells, Heart, Sap and Rings 163 How They Grow 163 How to Know Them 161 Trojan War 692 Tropical Life 121 Tropics: Animal Life of 121 Plant Life in 121 Trout 227 Troy Weight 861 Tudors, The 467 Tulip 149 Turkey 220, 292 (See also Turks, Ottomans.) Asiatic 572 Bagdad Railroad 577 Cities 574 Climate and Industry 573 Commerce 574 Constantinople 574 Dardanelles Campaign 577 European 573 Government of 574 History 576 People 574 Physical Features 573 Statistics about 572 Turkeys 260 Breeds of 260 Turks, or Ottomans 292 Conquer Byzantine or Eastern Empire 404 Historical Outlines 419 et seq. Turnip 131 Turquoise 112 Turtles 220 Sea 221 Snapping 221 Tusk Shells 230 Typhoons 93 Tyre 367

=U=

Udo 129 United States 579 Center of Population 587 Cities 590 Climate and Irrigation 587 Coast of 581 Colorado River 582 Congress of 656 Executive Departments of 654 Government 652-662 Great Central Plain 580 Great Lakes 583 Great Salt Lake 583 Historical Outlines 422 et seq. Hudson River 582 Islands 581 Judicial Department of 660 Lakes of 583 Legal Weights per Bushel 861, 862, 863 Money and Coins 868, 869 Mountains and Plains 580 Natural Wonders of 584 Outlines of Colonial History 628-633 Outlines of Period of Settlement 630, 631, 632, 633 Political Divisions 587 President, The 652 Public Lands 587 Races Represented in 293 Rivers 581 St. Lawrence River 582 Surface 579 Tables of States and Territories 558-590 Tables of the Presidents 662-665 United States History: Adoption of Constitution 637 American Independence Declared 636 Articles of Confederation 637 Assassination of Lincoln 644 Assassination of McKinley and Succession of Roosevelt 647 Campaigns and Battles of the American Revolution 636 Civil War of 1861-1865 642 Continental Congress 635 Democrats Restored to Power under Leadership of Woodrow Wilson 647 Early Troubles in Our System of Public Finance 639 Effect of French and English Struggles upon United States 637 Election of Hayes Decided by an Electoral Commission 645 Era of the Whigs 640 Fall of the Federalists 639 How Europe First Divided the Colonies 635 Lincoln and Rise of Republican Party 642 Map of Panama Canal and Connections 649 McKinley and the Spanish-American War 645 Mexican War and Annexation of Texas 640, 641 Norse Discoverers 634 Oppression of the Colonies under British Rule 635 Panama Canal 648 Period of Discovery 634 Period of Discovery and Exploration 628, 629 Period of Industrial Expansion 639 Period of Settlement 630-633 Preliminary Struggle over Slavery 640, 641 Resumption of Specie Payments by the Government 645 Revolution 635 Rise of “Protected Tariff” Policy 639 Rise of Slavery Issue 640 Secession of Southern States, and Formation of Confederacy 642 Settlement at Jamestown 634 Settlement of Carolinas 630-632 Settlement of Connecticut 630-632 Settlement of Delaware 631-633 Settlement of Georgia 632 Settlement of Maryland 630-632 Settlement of Massachusetts 630-632 Settlement of New Hampshire 630-632 Settlement of New Jersey 631-633 Settlement of New York 631-633 Settlement of Pennsylvania 633 Settlement of Rhode Island 630-632 Settlement of Virginia 630-632 Spanish-American War 646 Struggle of England and France for America 635 Taft and the Rise of the Progressives 647 War of 1812 638 Wilson Re-elected and His Policies Approved 648 Unter den Linden, Berlin 499 Upas Tree 165 Upsala 569 University of 569 Urals 446 Usury, Penalty for 875 Utah, Great Salt Lake 77

=V=

Valois, House of 494 Vapor, Atmospheric 94 Vatican Palace 516 Vegetable Kingdom 119 et seq. (See also Plants and Plant Life.) Botanical Classification of Plants, 182, 183, 184, 185, 186 Chief Divisions of 122 Cryptogams 158 Fiber and Commercial Plants 166 Flowering Shrubs and Plants 155, 156 Flowers and Other Ornamental Plants 147 Forest Trees 160 Fruit-bearing Shrubs and Plants 142 Fruit Trees 136 Kitchen Vegetables 128 Newest Grown Vegetables 129 Planting Tables 132, 133, 134, 135, 136 Poisonous Plants 168 Scientific Terms in Botany 176 Wonders of Plant Life 169 Venice 523-524 Campanile and Palace 522 Vernal Equinox 90 Versailles 483 Venus’ Fly-trap 169 Victorian Era 469 Victorian Period 768-775 Vicuna 202 Vienna 529 Industries of 531 Noted Buildings 530-531 Vines: Description of Desirable Annuals 154, 155 Desirable Annuals 154, 155 Vladivostok 545 Voice, Inflection of 716 Volcanoes 63 et seq. Location and Height 65 Most Noted 65 Vowels 712 Vultures 211

=W=

Walnut 142 Walrus 205 Wanderoo 194 War of the Austrian Succession 696 War of 1812 638 War of Greek Independence 697 War of Italian Liberation 697 War of the Holy Roman Empire 695 War of the Spanish Succession 696 Warblers 216 Wars, Great, Historical Outlines 312 et seq. Wars for Control of Italy 695 Wars of Alexander the Great 693 Wars of Constantine 694 Wars of the English Barons 695 Wars of Justinian 694 Wars of Louis XIV. 696 Wars of the Roses 695 Wars of Universal History 692-699 Warsaw 560 Washington, D. C. 623 Arlington House 626 Bureau of Engraving and Printing 624 Capitol 623 Catholic University of America 626 Census Bureau 625 Chief Shopping Streets 623 Churches and Educational Institutions of 626 Congressional Library 623-624 Continental Hall 625 Corcoran Art Gallery 624 Department of Agriculture 624 District or Municipal Building 625 Ford’s Theater 625 George Washington University 626 Georgetown University 626 Government Printing Office 625 History of 623 Interior Department 625 International Bureau of American Republics 625 Judiciary Square and Pension Office 625 Mount Vernon 627 National Military Cemetery (Arlington) 626 National Soldiers’ Home 626 New National Museum 624 Notable Public Buildings 624-625 Notable Residence Streets 623-624 Parks, Squares and Circles 623-624 Post Office Department 625 St. John’s Church 625-626 Smithsonian Institution 624 State, War and Navy Departments 625 Treasury Department 624 Trinity College for Women 626 Union Railway Station 623 United States Naval Observatory 626 Views of Washington’s Home and Tomb, Mt. Vernon 627 White House 625 Wasps 238, 240 Water: Composition and Forms of 69 How Distributed over the Earth 68 et seq. Water Hemlock 169 Waterfalls, Famous 80 Bridal Veil 83 Iguazu 82 Juanacatlan 82 Niagara 82 Reichenbach 83 Schaffhausen 81 Staubbach 83 Yellowstone 83 Yosemite 83 Watermelon 131 Wealth, of Nations 443 Weather 89 Weevil 234 Weights and Measures: Apothecaries’ Liquid Measure 860 Apothecaries’ Weight 863 Avoirdupois Weight 860 Calendar 866, 867 Capacity 860 Circular Measures 864 Comparison of 864 Cubic or Solid Measure 859 Dry Measure 860 Land Measure 858 Legal Weights per Bushel 861, 862, 863 Length 857 Liquid Measures 860 Long Measures 856 Longitude and Time 864 Of the Philippines 870 Square Measure 857, 858 Surface 857 Surveyor’s Measure 857, 858 Texas Land Measure 858 Time Measures 865 Troy Weight 861 United States Money 868, 869 Wellesley College 594 Westminster Abbey 460 Whales 207 Wheat 128 Whitefish 228 Wild Flowers 157 Wild Goat 202 Willow 165 Winds 92 Hurricane 93 Simoon 93 Sirocco 93 Storms 93 Tornadoes 93 Trade Winds 93 Typhoons 93 Windsor 464, 466 Winter Solstice 90 Wire-worms 234 Wolf 197 Prairie 198 Wolf’s-bane 169 Wonders, of Plant Life 169 Woodcock 218 Woodpecker 212 Words: Choice and Use of 717 From Modern Foreign Languages 742 Right and Wrong Use of 718, 724 World: About B. C. 3800, to B. C. 450, 296-301 About B. C. 450 301 About B. C. 325 301 About 300 A. D. 301 About 500 A. D. 302-303 About 800 A. D. 302-303 About 1000 A. D. 302-303 About 1300 A. D. 302-303 About 1500 A. D. 304-305 About 1600 A. D. 304-305 About 1700 A. D. 306-307 About 1800 A. D. 306-307 About 1915 A. D. 308-309 Asia 677 Colonial Divisions of 690 Greatest Explorers of 310-311 Independent, Countries of 443 North America 578 Political Divisions of 443 Principal Languages of 442 Races and Population 442 Religious Population 442 South America 672 Wrens 216

=X=

Xerxes the Great 370

=Y=

Yak 256 Yale University 605-606 Yam 131 Yellowstone Falls 83 Yellowstone National Park 586 Yew Tree 165 Yokahama 689 Yosemite Falls 83 Yosemite Valley 585

=Z=

Zama, Battle of 391 Zebra 203 Zebu 256 Zinc 115 Zwinger, The, Dresden 503

SUPPLEMENTARY INDEX

=A=

Acids 891-892 Aeroplanes 902 Airship, Modern 903 Zeppelins 903 Alcohol 892 Alimentary Canal, Diagram of 929 Alkali 892 Aluminum 883 Antimony 883 Argon 883 Arithmetic: Bank Discount 873 Chemical 882 Exchange 874 Interest 873 Percentage and Its Business Applications 870 Promissory Notes 872 Square and Cube Root 878 Taxes and Taxation 877 Arsenic 883 Astronomy, Outlines for Grade Schools 897 Atomic Theory 881

=B=

Bank Discount 873 Barium 883 Berthollet’s Law 882 Biography 943 et seq. Comparative and Chronological Tables 944-957 Bismuth 883 Boron 883 Botany, Outlines for Grade Schools 896 Brain 932 Bromine 884

=C=

Cadmium 884 Caesium 884 Calcium 884 Calomel 894 Carbon 884 Cerium 884 Chemical Elements: Compounds and Chief Uses 883 et seq. Important Data Concerning 883 et seq. Occurrence, Preparation and Properties 883 Table of 883 et seq. Chemicals, Common Names of 894 Chemistry 880 Atomic Theory 881 Berthollet’s Law 882 Chemical Arithmetic 882 Chemical Notation 881 Of Common Things 891 Importance and Divisions 880 Laws of 881 Molecular Weights 881 Nomenclature 882 Organic and Inorganic 880 Outlines for Grade Schools 897 Physical 881 Radicals 882 Reactions 881 Table of Chemical Elements 883 Theoretical 881 Chest or Thorax 930 Child World 959 et seq. The Art of Story Telling 987-988 The Bath 965 Bones and Muscles 964 Children’s Gardens 970 The Children of the Animals 973 The Child’s Food 963 The Child’s Lessons 963 Child’s Picture Grammar 971 Combinations of Numbers 983 Counting 982 The Days and Months 985 Dutch Dolls and the “Alphabet Game” 967 Effect of Seasons on the Nervous System 964 Form and Color 985-987 The Growing Body 961 How to Teach a Child to Read at Home 968-970 Money Taught as Numbers 983 The Mother as Teacher 960 Nature as the First Craftsman 976 Nature’s Best Doctors 962 Primary Measures for Children 984 Puberty and Its Problems 964 Rest and Sleep 964-965 The School Age 961 Stories, Illustrated 974-981 Telling the Time 984 Time for Work 963 Ventilation 965 What Our Domestic Animals Give Us 972 “Where Did You Come From, Baby Dear?” 966 Chlorine 884 Chromium 884 Circulatory System 930 Cobalt 884 Columbium 884 Commercial Law, Promissory Notes 872 Commission 871 Common Names of Chemicals 894 Compass, Mariner’s 912 Copper 885 Cranium 932 Cube Root 878 Customs Taxes 878

=D=

Dynamos and Motors 916 Dysprosium 588

=E=

Earth, Magnetic Poles of 912 Electric Cell, What Goes on Within 915 Electric Light 914 Electric Machines 916 Electric Telegraph, Principle of 916 Electric Traction 916 Electricity 907-911 Application of to Machines 916 Batteries 913-914 Currents 909 Dynamos and Motors 916 Electron Theory 908-909 How Produced 908 Lightning 909 Natural Exhibitions of 909-911 Theories About 907 Wireless Telegraphy 918 Electro-Magnetism 916 Electrons 908 Electrotyping 916 Erbium 885 Ether 892 Europium 885 Exchange 874 Domestic 875 Principles of 876

=F=

Fermentation 892 Fluorine 885

=G=

Gadolinium 885 Gallium 885 Galvanic, or Voltaic Battery 913, 914 Galvanism 913 Galvanometer 913 Gas Meter, How to Read 895 Gateways of Knowledge 933 Geology, Outlines for Grade Schools 897 Germanium 885 Glucinum 885 Gold 885

=H=

Heart 933 Heart and Its Coverings 930 Helium 885 Holmium 886 Human Body 925 et seq. Alimentary Canal 929 As a Machine 927 Centers of Control 927 Circulatory System 930 Divisions of 927 Framework and Muscles of 926 Health in Childhood 961 Heart and Its Coverings 930 How It Is Built 927 Nervous System 932 Organs of Chest 928 Puberty and Its Problems 964 Respiratory System 931 Systems and Organs 927 et seq. Human Brain 933 Hydrogen 886

=I=

Indium 886 Interest 873 Common Methods 873 Compound 874 Table of Time 874 Inventions, Great Mechanical 898 Iodine 886 Iridium 886 Iron 886

=K=

Krypton 886

=L=

Lanthanum 886 Lead 886 Lightning, a Form of Electricity 909 Liquid Air 924 Lithium 886 Loadstone 911-912 Locomotive, Description and Types 901-902 Electric 902 Skeleton and Parts of 900 Lungs 931 Lutecium 887

=M=

Magnesium 887 Magnetism 911 Magnetic Poles of the Earth 912 Relation to Electricity 911, 912, 913 Magnets 912, 913 Manganese 887 Mariner’s Compass 912 Mercury 887 Meteorology, Outlines for Grade Schools 897 Mineralogy, Outlines for Grade Schools 896 Molybdenum 887

=N=

Neon 887 Neodymium 887 Nervous System 932 Nickel 887 Nightingale, Florence 958 Nitrogen 887 Notes: Legal Rules Concerning 872 Promissory 872

=O=

Osmium 887 Oxygen 887

=P=

Palladium 888 Percentage and Its Business Applications 870 Bank Discount 873 Commission 871 Exchange 874 Profit and Loss 871 Promissory Notes 872 Stocks and Bonds 876 Taxes and Taxation 877 Trade Discount 871 Pericardium 930 Periscope, The 905 Phosphorus 888 Physics and Chemistry, Outlines for Grade Schools 897 Physiology 925 et seq. Platinum 888 Potassium 888 Praseodymium 888 Profit and Loss 871 Promissory Notes 872 Property and Its Problems 964

=R=

Radium 888 Description of 894 History and, Properties 894-895 Medical Uses of 895 Red, Cross, Woman Founder 958 Respiratory System 931 Rhodium 888 Röntgen, or X-rays 921-923 Rubidium 888 Ruthenium 888

=S=

Samarium 889 Scandium 889 Science, Outline Course of Elementary 896-897 Science, Outlines, for Schools 896-897 Selenium 889 Silicon 889 Silver 889 Sodium 889 Special Senses: Hearing 933-935 Seeing 936-938 Smelling 940-941 Taste 939, 940, 941 Touch 941-942 Organs of: Ear 933-935 Eye 936-938 Hand 941-942 Nose 940-941 Tongue 939, 940, 941 Spinal Cord 932 Spinthariscope 895 Square Root 878 Starch 891 Steam Engines 898 Stocks and Bonds 876 Strontium 889 Submarines 904 How Equipped 906 Marvelous Mechanism 904 The Periscope 905 Torpedo Tube 906 Sulphur 889 Sympathetic System 932

=T=

Tables, Interest 874 Tantalum 890 Taxes and Taxation 877 Taxes: Customs 878 Table of Tax Values 878 Teeth and Their Names 933 Teeth, Permanent 933 Telegraph, Electric, Principle of 916 Tellurium 890 Terbium 890 Thallium 890 Thorax 930 Thorium 890 Thullium 890 Tin 890 Titanium 890 Torpedoes, How Launched by a Submarine 906 Trade Discount 871 Tungsten 890 Turbines, Steam 899

=U=

Uranium 890

=V=

Vanadium 890 Vocal Cords 931 Voice, Organ of 933

=W=

Wireless Telegraphy 917, 918, 919 Wireless Telephony 920

=X=

Xenon 891 X-rays 921-923

=Y=

Yeast 892 Ytterbium 891 Yttrium 891

=Z=

Zeppelins 903 Zinc 891 Zirconium 891 Zoology, Outlines for Grade Schools 896

Transcriber’s Notes:

General Notes

The different sections of the book were written by different authors; inconsistent spelling, lay-out, capitalisation, phonetics, use of ligatures and diacritics, spacing of abbreviations, transcription, punctuation, etc. have therefore been retained (incl. canon/canyon/cañon; Spencer/Spenser; i.e./i. e., A.D./A. D., etc.) except as mentioned below. The same applies to textual and factual inconsistencies and contradictions.

The order of entries in alphabetical lists is not always truly alphabetical; this has not been changed.

Indented paragraphs in this text indicate a different lay-out in the printed work, such as larger or smaller font size, different margins or indentation, etc. Not all of these differences have been indicated in this text.

The use of section headings in the printed work was not always unambiguous, nor was their hierarchy. Section headings (indicated by two blank lines in this transcription) in this text are therefore based on the printed book’s typography and on apparent logic, and may not reflect the authors’ intentions. Some sections have no section headings as such.

Several subjects mentioned in the various lists of contents are not present in the original work; similarly, several internal references do not exist.

In some of the larger tables, the relation between table elements has had to be surmised; the tables as presented here may therefore not fully reflect the authors’ intent.

For this text version, the larger tables have had to be split and/or re-arranged. For the comparison tables in particular, this means that some of the comparative information has been lost.

Specific Notes

Page 104-107, Table Identification of Minerals, See Plate I: there is no Plate I with figures of minerals in the original work.

Page 158, Flowers of the Wooded Pastures: the referenced Fig. 13 is not present in the original book.

Page 267, Book of Races and Peoples: various district names is probably an error for various distinct names.

Page 293, table Comparative Classification of Races and Peoples: Fellaheen, 5,000,000 ( ): the reason for the brackets is not clear.

Page 360, Fall of Judah and Babylonian Captivity: The history of the Jews during the Babylonish captivity: this was printed as a regular paragraph in the original book, but could have been intended as a heading for a section that was not included in the book.

Page 413, Table IX.: St. Francis of Assisi should probably have been printed in the columns Italy and Church.

Page 423, Table XI., column Ottoman Empire and Persia, War with Austria 1682-1699: possibly this should read 1593-1669 (the 1682 war is mentioned on page 425, Table XII.).

Page 442, table Principal Languages Spoken: The data for English and French are identical, which is probably an error. The totals and proportions are not in agreement with the tabulated data; since it is not clear which data are wrong, this has not been changed.

Page 448-452, Panoramic View of the River Rhine: texts inside the illustration have been copied outside the illustration.

Page 472-476, Table of the Sovereigns of England: There are some discrepancies between dates of birth and ages; not changed.

Page 474, Table of the Sovereigns of England: Edward VI., “Of a consumption”: as printed in original book.

Page 495, GERMANY: ... on a subsequent page: the table is given on the same page.

Page 497, Defense: reference to Armies and Navies of the World: not present in the original book.

Page 546, Under Peter the Great: reference to Peter the Great: unclear to which part of the text this refers, as there is no separate section on Peter the Great apart from this one.

Page 546, Napoleonic Period: reference to Alexander I. and Napoleon: unclear to which part of the text this refers, as there are no separate sections on Alexander I. and Napoleon.

Page 572, Turkey, or Ottoman Empire (table): population numbers do not add up to the total given (possibly the total should read 20,180,000); the meaning of the sentence directly underneath the table is not clear.

Page 573, Physical Features: reference to Asia Minor: there is no section on Asia Minor in the book.

Page 648, Democrats Restored ... Woodrow Wilson: there are two footnote anchors on this page in the printed book (before Farm Loan Banks and before From the very beginning of the European War), but no footnotes. The anchors have been deleted.

Page 714, Accent of Words: In the Book of Language and Literature primary and secondary accents are represented by =´= and ´, respectively. The print quality of the original work was not always sufficient to distinguish between the two variants.

Page 733, Asterism: the printed book shows two asterisms; possibly one of those was intended to be an inverted asterism.

Page 744, à rivederci: as printed in original work; not changed.

Page 745, carnichons: error for cornichons; not changed.

Page 753, recherche: possibly error for recherché; not changed.

Page 771, 18th century (Pepys): probably error for 17th century; not changed.

Page 783, Aldine Press: reference to Manutius: there is no other occurrence of Manutius in the book.

Page 788, Chriemhild or Kriemhild: reference to Kriemhild: this entry seems to reference itself.

Page 796, Folk: reference to Fairies: there is no entry Fairies (or Fairy) in the book.

Page 821-845, Pronouncing Dictionary of Myhtology: this section contains several references to entries that are not present in the work.

Page 856, Find the cost of 3230 bushels of wheat, at 72c per bushel: the calculation given is for 3230 pounds (with 60 pounds per bushel).

Page 857, Long or Linear Measure: reference to Metric System: not present in the book.

Page 878, Tax Table, Explanation of Table: the entry for $10,000 is not present in the table.

Page 894, Describe radium and its special properties: the printed book uses subscripts as exponents; not changed.

Page 763-764, Norman-French Period and Elizabethan and Puritan Period: there is no description of the period between these two (1400-1559) in the original work.

Changes and corrections made

Obvious minor punctuation and typographical errors have been corrected silently.

Regularly printed scientific names have been italicised for consistency.

Some diacritical symbols on French and German words have been corrected or added for consistency.

Some phonetics have been corrected or completed where this was important for their pronunciation, this has not been done for consistency.

Illustrations and tables have been moved out of the text when they were printed inside paragraphs; footnotes have been moved to directly underneath the paragraph or table to which they belong.

Various pages: Pharoah has been changed to Pharaoh.

Comparative History of Nations: several entries have been moved to maintain the given chronological order.

Indicator letters have been added to some pronouncing dictionaries for consistency.

Page iv PD.D. changed to PH.D. (Susan Chase) Page ix Mother-Play Sons changed to Mother-Play Songs Page 10 Vanderwolker changed to Vanderwalker Page 15 diagrams Keppler’s Laws: right and left in caption changed to bottom and top, respectively; moves round the run changed to moves round the sun Page 27 Pullox changed to Pollux Page 37 Pullox changed to Pollux Page 49 Age Fishes changed to Age of Fishes Page 62 Cypress changed to Cyprus Page 67 severally shaken changed to severely shaken Page 75 Pebblshire changed to Peeblesshire; Chevoit changed to Cheviot Page 85 internal changed to interval Page 106 row Orthoclase, 2nd column: repeated mention of Feldspar deleted Page 108 Ship dip changed to Sheep dip Page 150 Minulus luteus changed to Mimulus luteus; 4 inches changed to 4 weeks (Giant Spider Plant) Page 151 Colhicum changed to Colchicum Page 162 a common tree changed to is a common tree Page 182 Dicotoledons changed to Dicotyledons Page 195 does not effect changed to does not affect Page 250 Red Poles changed to Red Polls Page 252 recenants changed to revenants Page 255 Chevoit changed to Cheviot Page 256 large of “lard” changed to large or “lard” Page 258 botlong, changed to both long.; fois-gras changed to foie-gras Page 273 Early Iron Age: 100 to 500 B.C. changed to 1000 to 500 B.C. Page 312 Caucuses changed to Caucasus Page 316 Lake Mœ is changed to Lake Mœris Page 317 604-651 changed to 604-551 Page 318 Perides changed to Pericles Page 322 Asdrubal changed to Hasdrubal for consistency Page 332 B. C. changed to A. D. (table header) Page 333 B. C. changed to A. D. (table header) Page 341 Crete lost the Arabs changed to Crete lost to the Arabs Page 342 See pages 000, 000 changed to See page 351 (description of the sphinx) Page 343 Header EXTINCT NATIONS OF THE PAST added as in tables of contents Page 349 the good Anubis changed to the god Anubis Page 382 LATER HISTORY OR changed to LATER HISTORY OF Page 397 At Alexander changed to At Alexandria Page 398 SEPIDUS changed to LEPIDUS Page 410 Entries for Danish Kings and Canute the Great placed in chronological order; Rhœtia changed to Rhætia Page 420 Frances defeated changed to Francis defeated Page 427 1756-1763 changed to 1754-1763; 1678 changed to 1768 Page 428 Prussia and Austria, 1711 changed to Prussia and Austria, 1781 Page 438 Fallierès changed to Fallières Page 440 Poincarè changed to Poincaré Page 442 table Area and Population: 7.05 changed to 7.55, 48.02 changed to 48.20, 29.9 changed to 28.2; table Religious Population: 36,000,000 changed to 36,600,000; 58,270,000 changed to 158,270,000; 125,000,000 changed to 25,000,000 Page 443 Poincare changed to Poincaré; Vagiravudn changed to Vagiravudh Page 446 Orœfa changed to Oræfa Page 463 Axon changed to Avon Page 464 Chantry changed to Chantrey Page 471 table (entry Mauritius): Executive and Councils changed to Executive and Legislative Councils Page 473 table (entry King John): 199 changed to 1199 Page 492 Marsla-Tour changed to Mars-la-Tour Page 525 Placenza changed to Piacenza Page 562 are said to be abundance changed to are said to be abundant Page 571 Rhœto-Romanic changed to Rhæto-Romanic Page 662 One of more changed to One or more Page 669 Caspé changed to Gaspé Page 693 Decclea changed to Decelea Page 696 Jan van Olden, Barneveldt changed to Jan van Oldenbarneveldt Page 700 Chattanooga, Georgia changed to Chattanooga, Tennessee Page 701 (Bosworth Field): 1845 changed to 1485; (Siege of Calais): =English= vs. =French= changed to =English= vs. French Page 702 kon-stan-nō´pl changed to kon-stan-ti-nō´pl Page 703 zhe-mäk´ changed to zhe-mäp´; Hōchst changed to Höchst Page 705 nü´pö changed to ma´pö Page 709 Texel: † added Page 734 paragraph * Name-making ... moved up one paragraph Page 741 5th ◡ changed to ― (Iambic pentameter) Page 742 desprit changed to d’esprit Page 743 albuon changed to al buon Page 750 sono multi changed to sono muti (also in phonetics) Page 751 mennière changed to meunière (and moved to proper alphabetical place) Page 752 petits fois changed to petits pois (also in phonetics) Page 753 enchef changed to en chef Page 754 tâche sans tâche changed to tâche sans tache Page 770 Ecclestical changed to Ecclesiastical Page 775 Rosetti changed to Rossetti Page 778 effected changed to affected; Calvanism changed to Calvinism Page 780 Bigelow changed to Biglow Page 799 Whence these storied changed to Whence these stories Page 802 Kadr, Al changed to Kadir, Al Page 810 chantler changed to cantler Page 816 Altorf changed to Altdorf Page 847 Amphlon changed to Amphion Page 853 7/9 + 4 changed to 7/9 × 4; 1-11/27 changed to 1-11/24 Page 854 .564 changed to 564 (in first multiplication) Page 855 $43.35 changed to $4.35 as in calculation Page 859 For, changed to For example, Page 882 (3) inserted before Metathetical Page 885 M. P. 272° changed to M. P. -272° (Helium) Page 886 ZuS changed to ZnS (zinc blende) Page 887 MgSO₄, 7N₂O changed to MgSO₄, 7H₂O Page 888 CaH₄(PO₄)₂ changed to CaH₂(PO₄)₂ Page 891 B. P. 109° changed to B. P. -109° (Xenon) Page 894 N₄H.OH changed to NH₄OH Page 998 Petsal changed to Petsai

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The Circle of Knowledge: A Classified, Simplified, Visualized Book of Answers (part 9 of 9)

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The Circle of Knowledge: A Classified, Simplified, Visualized Book of Answers (part 9 of 9)