Agricultural engineering

Front matter

V

CV Y * f) ^i-.

,0° v *

Preface

Believing that the study of Agricultural Engineering should fill an important place in the training of the young man who would make farming the object of his life's work, the author has attempted to furnish in this volume an aid in supplying this part of his training. The application of agricultural engineering methods to agriculture should not only raise the efficiency of the farm worker but should also provide for him a more comfortable and healthful home.

This volume has been written primarily as a text for secondary schools of agriculture, and for colleges where only a general course can be offered. Claim is not. made for much new material concerning the subjects discussed; but rather an attempt has been made to place under one cover a general discussion of agricultural engineering subjects which hitherto could not be secured except in several volumes and hence impractical for text-book purposes.

No attempt has been made to outline the exact method for the teaching of the subjects, as this must vary with conditions. It is desirable that classwork upon the text should be supplemented by laboratory work. The nature of the laboratory work will depend upon the equipment available. It is suggested that the equipments on the nearby farms may be used to good advantage. Sample machines to be used for study may be secured by co-operation with dealers in farm machinery.

The author will be very glad to receive criticisms and suggestions from those using this text, in regard to how it may be improved and made more useful. The correction of any errors will likewise be appreciated.

8 PREFACE

Although written primarily for use as a text book, it is hoped that this volume will be of interest to those engaged in practical agriculture.

Many of the illustrations were made from photographs secured from the files of the Iowa State College. In addition, the trade literature of the following manufacturers was drawn upon :

International Harvester Company of America; John Deere Plow Co. of Moline, 111.; Moline Plow Co.; W. & L. E. Gurley; Eugene Dietzen Co.; Keuffel and Esser Co.; Parlin and Orendorff Co. ; Fairbanks, Morse and Co. ; Hayes Pump and Planter Co. ; Hunt, Helm, Ferris & Co. ; J. D. Tower and Sons Co. ; Western Wheeled Scraper Co. ; Pattee Plow Co.; Avery Company; Emerson-Brantingham Co.; M. Rumely Co. ; American Seeding Machine Co. ; Oliver Chilled Plow Works; Hart-Parr Co.; Red Jacket Mfg. Co.; A. Y. McDonald Mfg. Co. ; Louden Machinery Co. ; Gale Mfg. Co. ; Sandwich Mfg. Co.; Aspenwall Mfg. Co.; Wilder-Strong Implement Co. ; Port Huron Engine and Thresher Co. ; J. L. Owens Co.; Charles A. Stickney Co.; Twin City Separator Co.; Cushman Motor Works; F. E. Meyers & Bro.; D. M. Sechler Carriage and Implement Co.; Roderick Lean Mfg. Co.; Janesville Machine Co.; LaCrosse Plow Co.; The John Lanson Mfg. Co.; J. I. Case Plow Works; J. I. Case Threshing Machine Co. ; Johnson & Field Mfg. Co. ; Racine Sattley Co. ; Kewanee Water Supply Co. ; and others.

Valuable assistance was secured from Mr. M. F. P. Costelloe, Associate Professor of Agricultural Engineering, Iowa State College, who read the manuscript for Parts I to IV, inclusive. Mr. J. H. Weir, the Editor, did very efficient work on the manuscript, which is appreciated.

Ames, Iowa. J. B. Davidson.

February, 1913.

Definitions and Uses of Surveying

Measuring — -The Use, Care, and Adjustment of

the Instruments

Field Methods

Map Making

Computing Areas

The United States Public Land Survey Instruments for Leveling; Definitions . Leveling Practice

PART II— DRAINAGE Principles of Farm Drainage The Preliminary Survey

Laying Out the Drainage System Leveling and Grading Tile Drains Capacity of Tile Drains

Land Drainage

Construction of Tile Drains Open Ditches .....

Drainage Districts

Page 13

18 24 28 34 38 42 49

56 64

67 73 78 86 96 103 108

Page

Importance of Roads ...... 141

Earth Roads 147

Sand-Clay and Gravel Roads .... 153

Stone Roads 160

Road Machinery 167

Culverts and Bridges 175

PART V— FARM MACHINERY The Relation of Farm Machinery to Agriculture .... 180

Definitions and Principles .... 186

Materials 195

The Plow 199

Harrows, Pulverizers, and Rollers . . 211

Seeders and Drills 223

Corn Planters 231

Cultivators 237

The Grain Binder or Harvester . . . 244

Corn Harvesting Machines 251

Hay-Making Machinery 258

Machinery for Cutting Ensilage .... 273

Threshing Machines 278

Fanning Mills and Grain Graders . . . 282

Portable Farm Elevators 287

Manure Spreaders 292

Feed Mills and Corn Shellers . . . 298

Spraying Machinery 303

The Care and Repair of Farm Machinery . 309

Part Vi— Farm Motors

Elementary Principles and Definitions . . 313 Measurement of Power . . . . . 316

Transmission of Power ' . 320

The Horse as a Motor 327

Eveners 334

Windmills 339

The Principles, of the Gasoline Engine . . 344

CONTENTS

Chapter Page

LV. Engine Operation ....... 350

LVI. Gasoline and Oil Engine Operation . . . 354

LVII. Selecting a Gasoline or Oil Engine . . 361

LVIII. The Gas Tractor 370

LIX. The Steam Boiler 376

LX. The Steam Engine . . • 385

LXI. The Steam Tractor 389

Part Vii— Farm Structures

LXII. Introduction and Location of Farm Buildings . 395

LXIII. Mechanics of Materials 402

LXIV. Mechanics of Materials and Materials of

Construction 406

LXV. Hog Houses 414

LXVI. Poultry Houses 425

LXVII. Dairy Barns . . . . . . . .436

LXVIII. Horse Barns 442

LXIX. Barn Framing 445

LXX. The Farmhouse 451

LXXI. Constructing the Farmhouse .... 455

LXXII. The Silo 461

LXXIII. The Implement House and Shop . . . 473

Part Viii— Farm Sanitation

LXXIV. The Farm Water Supply 480

LXXV. The Pumping Plant 486

LXXVI. Distributing and Storing Water . . . .491

LXXVII. Plumbing for the Country House . «. . 497

LXXVIII. The Septic Tank for Disposal of Farm Sewage . 501

LXXIX. The Natural Lighting of Farm Buildings . 506

LXXX. Lighting the Country Home 510

LXXXI. The Acetylene Lighting Plant .... 515

LXXXII. The Electric Lighting Plant 520

LXXXIII. Heating the Country Home .... 525

LXXXIV. Ventilation of Farm Buildings .... 531

PART IX— ROPE WORK LXXXV. Ropes, Knots, and Splices 537 INTRODUCTION

Engineering. Denned briefly, engineering is the art of directing the forces of nature to do economically the work of man. The pursuit of agriculture requires many mechanical operations whose execution involves the use of engineering methods.

Consider the production of wheat. The plowing, the pulverizing and smoothing of the soil, the cleaning and grading of the seed, the drilling of the seed, the harvesting, the thrashing, and the hauling of the crop to market, are all mechanical operations to which the skill of the mechanic or engineer should be applied in order to obtain the best results.

In like manner if the production of other crops be considered, it will be found that there are many operations to be performed in connection therewith, which will require the directing of the forces of nature or the application of engineering principles.

Agricultural Engineering. In the broadest sense, agricultural engineering is intended to include all phases and branches of engineering directly connected with the great industry of agriculture. In America it is only recently that the term agricultural engineering has come into general use. The term rural engineering is used by some to designate the same subject.

It is only within the last few years that the importance of agricultural engineering as a branch of agricultural education has been recognized. A knowledge of soils and of the plants and animals of the farm is essential to those who would make good farming the aim of their life's work, and these subjects should be carefully studied by the agricultural student. But the study of agricultural engineering is quite as important in assuring that efficiency in farm management which results in the greatest and most permanent benefits.

The truth of the foregoing statement is better understood when one learns that the producing capacity or earning ability of the farm worker is in direct proportion to the amount of power he is able to control. There was a time when man tilled the soil by his own individual efforts, depending upon no other source of power than the strength of his own body. Later, one beast per worker was pressed into service to draw suitable implements. Still later, two animals were used, and development has continued, until at the present time we have reached the "age of four-horse farming." In other words, the four-horse team is now recognized as the most efficient one for field work.

Man as a motor or producer of power is able to develop about one-eighth of one horsepower. When use was made of one good horse per worker, man's labor capacity was increased eightfold. When four horses became the unit, his efficiency was multiplied about 32 times. Just now there is a desire to increase still further the amount of power for each farm worker, by the use of powerful tractors or engines arranged for drawing and operating farm implements.

The application of power to farm operations, which must come mainly through the use of machinery, is only one branch of agricultural engineering. Some element of agricultural engineering is concerned in nearly every department of agricultural endeavor. It serves man in one or both of two ways : (1) By making it possible to increase the capacity of the worker, as just explained; and (2) by making condi-

INTRODUCTION 15

tions more desirable and satisfactory, either by relieving the worker of hard labor, or by providing more healthful and pleasing surroundings.

Farm Mechanics. The term Farm Mechanics is not as comprehensive in meaning as Agricultural Engineering, yet it is often used to designate the same branch of education. Mechanics is the science of forces and their actions; whereas engineering proper is based upon a knowledge of these forces and treats more particularly of the directing of them to secure their most advantageous use.

In this text the subject of agricultural engineering is presented under the following heads :

Agricultural Surveying.

Drainage.

Irrigation.

Roads.

Farm Machinery.

Farm Motors.

Farm Structures.

Farm Sanitation.

The importance and relation of these various branches to agriculture are discussed in the separate parts of the text devoted to each.

1. Define the term engineering.

2. Show how engineering methods are involved in crop production.

3. Define the term agricultural engineering.

4. Is there any relation between the producing capacity of a farm worker and the amount and kind of power used?

5. Distinguish between "farm mechanics" and "agricultural engineering."

6. Name the principal branches of agricultural engineering.

Chapter I Agricultural Surveying

Surveying. The object of agricultural, or land, surveying, in its generally accepted meaning, is to determine and place on record the position, area, and shape of a tract of land. The various steps taken to accomplish this end constitute a survey. In addition to the field work with instruments for measuring distances, angles, and directions, a field record, containing figures, notes, and sketches concerning the work must be kept; the areas must be computed; and usually a map, plat, or profile made showing the tract of land surveyed. The art of land surveying includes all of these various lines of work.

Uses of Surveying. Agricultural students can well afford to spend some time in the study of land or agricultural surveying. The object of the work here presented on surveying is to enable the student to measure and calculate accurately the areas of the various fields of the farm and to locate the buildings; to prepare a good map setting forth the relative size and position of the fields, buildings; and fences, and indicating the drains; and to prepare the student for the study of drainage and irrigation.

It is necessary for the farmer to know the areas of his fields in order that he may determine accurately the yields of the various crops grown. A survey will enable the farmer to so divide his farm into fields as to facilitate a system of crop rotation.

A good map is a means of recording the location of drains and water pipes laid beneath the surface of the ground. It will also enable the farmer to direct the work of the farm more easily, and to make a study of the most convenient arrangement of fields and buildings. This method is used by architects and engineers in planning buildings and engineering work such as factories and railroads.

Divisions of Agricultural Surveying. The work of making a survey resolves itself into three stages or operations, as follows :

1. Measuring and recording distances and angles, involving the use, care, and adjustment of the instruments used in the survey.

2. Drawing the tract surveyed to a suitable scale, or proportion.

3. Calculating the areas of the tracts surveyed.

1. What is the object of agricultural surveying?

2. Define a survey.

3. To what use can a knowledge of surveying be put by those connected with agriculture?

4. In what way will a map be of use to the land-owner?

5. Describe the three divisions of agricultural surveying.

Chapter II Measuring; Use And Care Of Instruments

Instruments for Measuring Distances. Often students are led to think that it is impossible to make a survey without a very elaborate equipment of expensive instruments, but this is not true. An agricultural survey, such as is usually required by the farm owner or manager, can be accomplished with simple and quite inexpensive instruments. Where the boundary of the tract of land is known, a practical survey may be made with a surveyor's chain or tape.

Gunter's, Chain. Much of the land in the United States was surveyed originally with the Gunter's chain, which is now but little used. This chain is 66 feet long, divided into 100 links, each of which, including the connecting rings at the ends, is 7.92 inches long. The links are made of steel or iron wire, and the better chains have the open joints soldered or brazed together. The reason for making the Gunter's chain of the length of 66 feet or 100 links is owing to its convenient relation to the standard units of length and area in use. The chain is 1-80 of a mile, or two rods. A square chain is 1-10 of an acre. Thus ten square chains make an acre, and this, together with the fact that links may be written as a decimal of a chain, greatly facilitates computations. To illustrate, 1625 square chains equal 162.5 acres, and 15 chains and 24 links equal 15.24 chains.

Fig. 1. The Gunter's chain, folded.

The Gimter's chain has been used on all United States land surveys; and in deeds of conveyance and other legal documents, when the word chain is used, the Gunter's chain of 66 feet is meant.

Table of Linear Measure.

12 inches (in. or ") make 1 foot (ft. or ')

3 feet " . 1 yard (yd.)

5 l A yards or 16^ feet " 1 rod (rd.)

320 rods " 1 mile (mi.)

Equivalent Table

Mi. Rd.

Yd. Ft.

In.

1 320

1760 5280

63360

5V 2 1VA

1 3

Table of Gunter's Chain Measure.

7.92 inches (in.

or ") make 1 link

100 links

" 1 chain (ch.)

80 chains

" 1 mile

Equivalent Table

Mi. Ch.

Li.

In.

1 80

63360

7.92

Table of Surface Measure.

141 square inches (sq. in.) make 1 square foot (sq. ft.)

9 " feet "1 " yard (sq. yd.)

30M " yards " 1 " rod (sq. rd.)

160 " rods " 1 acre

Equivalent Table

A.

Sq. rd.

Sq. yd.

Sq. ft.

Sq. in.

43560

6272640

30^

272 14

39204

1296 144

Surveyor's Measure.

625 square links (sq. li.) make 1 square rod (sq. rd.) 16 " rods " 1 " chain (sq. ch.)

10 " chains " 1 acre

640 acres " 1 square mile, or one section

Equivalent

Table

Sq. oh.

Sq. rd.

Sq. li.

100,000

10,000

Cloth and Metallic Tapes. Tapes made of linen cloth are not practical to use in land surveying, even when well made and water-proofed. They will stretch when pulled up tight, and are difficult to handle in the wind. A cloth tape is much improved when small brass wires are woven lengthwise into it to check the tendency to stretch. Such a tape is said to be a metallic tape. These tapes are made to wind into a case of sheet metal or leather, and for this reason are very convenient to carry about.

Steel Tapes. The steel tape is now the standard measuring instrument, as it has many advantages. It does not kink, stretch, or wear so as to change its length.

The steel tape may be obtained in lengths varying from 3 feet to 1000 feet. These tapes may be marked or graduated in any form desired.

The two common methods of marking the tape are by either etching the surface with acid, or stamping the marks on solder placed on the tape at the desired places. A tape

Fig-. 2. A metallic tape.

This tape has brass or copper wires woven into it lengthwise.

3. A steel tape wound on a reel.

100 feet long is usually termed the engineer's tape, and either this length or the 50 foot tape is the most convenient.

The average width of the steel tape is 5-16 of an inch, and the thickness about .02 of an inch.

Short tapes are arranged to be carried in metal or leather cases, but longer tapes are carried either on reels or are "thrown" into a coil from which they can be unwound without danger of kinking.

Arrows, or Marking Pins. For marking points temporarily while measuring with a tape or chain, arrows, or marking pins, are used. These are made of stout wire, pointed at one end, with a large eye or ring at the other. In order that the pins may be easily found in the grass or leaves, a piece of colored cloth should be tied to the rings. Eleven pins are required for a complete set, and are best carried on a ring Arrows, with a spring catch.

Range Poles or Flagstaffs are used to locate points in establishing a line. They are rods or poles usually 6 to 10 feet 'long, made of wood or iron, pointed so as to be easily planted in the ground, and painted red and white alternately in foot sections.

Flagstaffs should be placed directly over the points they are to mark, and great care should be used to plant them truly vertical. Much skill may be attained by practice in establishing lines with flagstaffs, and this skill will be found very useful in laying out fields, fences, etc.

4. or pins.

The Care and Use of Chains and Tapes. The chain is folded by starting at the middle and folding in the two halves at the same time. It is opened by holding the two handles in one hand and throwing out the chain with the other. The steel tape is wound on a reel or thrown into a coil, the latter method requiring some practice and skill to prevent kinks. Chains and tapes are used in measuring horizontal distances; and for this purpose they should be held horizontal, or level, when measuring, not parallel to the surface of the ground. The chain or tape should be pulled taut enough to overcome the shortening due to the sag. Where distances are to be obtained with great accuracy, the chain or tape should be tested often over a known fixed distance to determine the amount of pull necessary to bring it to the true length. Chains in constant use require frequent adjustment for wear.

Each pin should be so placed that its thickness will not be added to the length of the chain. Care should be taken to set the pins vertical. When chaining up or down slopes, one end of the chain must be held high to make it level, when it becomes necessary to transfer a point from the elevated end vertically to the ground. This can best be done with a plumb-bob and string, and a wooden when this is not at hand a pin may be dropped

range pole.

from the elevated end of the chain or tape and the point where it strikes the ground noted.

In chaining practice, the man leading is called the head chainman, and the other the rear chainman. In beginning a measurement, the rear chainman marks the starting point with one of the eleven pins in the set, and gives the remaining ten to the head chainman, who counts them. The head chainman then leads away with the chain or tape toward the point to which the distance is to be measured. When the rear end of the extended tape is near the starting point, the rear chainman calls "chain" or "tape," as signal for the head chainman not to go too far. The chain is then stretched full length, and the rear chainman lines the front chainman with the objective point by motioning with his head or otherwise indicating the direction he should move. When the head chainman has the chain in line, the rear chainman calls "stick," indicating that he has the chain to the pin. The head chainman then pulls the chain tight, and sets a pin, calling "stuck." The rear chainman pulls the rear pin, and both men move ahead and repeat the operation from the second pin; and so on. When the head chainman has placed his ten pins, he calls "tally," and waits for the rear chainman to walk forward to him and give him the ten pins he has collected.

Pacing. The ability to estimate distances accurately by pacing is often useful. Skill may be developed by pacing known distances until the length of the individual pace is determined and can be regulated.

1. What instruments are needed in making a practical survey of a tract of land where the boundaries are known?

2. Describe the Gunter's chain.

3. Recite the four tables used in measuring surfaces.

4. Describe the differences in tapes.

5. Describe the use of range poles. Of marking pins.

6. How is the chain cared for? The steel tape?

7. Describe the process of chaining.

8. In what way will the ability to estimate distances by pacing be useful?

Chapter III Field Methods

Making Chain Surveys. For many practical purposes a survey made with the tape or chain alone will be quite satisfactory. To make such a survey for area, the land is divided into rectangles or triangles, or both. The areas of any of these may be easily calculated when the length of each side is known.

Making Notes. In all surveys, all figures, notes, and

sketches should be systematically recorded in a suitable book, and these go to make what is called field notes. From these notes the map is later made and the areas calculated.

The most simple method of making field notes is to make a free-hand sketch of the field as nearly correct as the eye can determine. All corners should be designated by letters and the same marked on the sketch, which is used as a guide. All distances between corners should be recorded, not only in the sketch, but also in suitable columns. The points where fences, streams, and roads are crossed in measurement should be noted on the sketch. If the tract surveyed is so large that the sketch is likely to become confused, the entire

SURVEY or FIELD

A BCD WITH TAPE

AB BC CO DE EA BE SO

Head chainman R.Roe Rear chainman 1. Do e

Sept./ igii - J hrs- Cloudy and cool

Used steel tape looft.

Measured each side

in turn once c

A

E

Fig-. 6. A form for field notes.

tract may be sketched on one page, and details of certain parts on other pages.

All field notes should be carefully recorded in a well-bound, durable, and convenient field book. The standard field book has pages about 4 by 7 inches, ruled in any one of the several forms of ruling, and is substantially bound. The notes should be neatly made with a hard pencil in order that they will not blur with use. In the sketches, the customary symbols employed in map making may be used. These will be described later.

Field Methods. In making a chain survey, it is to be remembered that since angles are not measured, more measurements will be required. Many fields are rectangular, and their measurement is correspondingly simple. When the angles are not right angles they may be determined by measuring three sides of a triangle laid off in the corner, making two sides or the legs of the triangle coincide with the sides of the field.

Marking Points in a Survey. In making a survey all the important points should be marked for future reference. In laying out fields and lots, some permanent mark should be set at the corners. If a corner post is not used, a stone or a block of concrete should be set in the ground and a cross chiseled on the surface to indicate clearly the point. Stakes of durable wood may be used to good advantage. The exact point may be indicated by driving a tack in the top of the stake. A stake two inches square is often

i mi r- i i , i *l.- j.1 Fi %- "'■ Sketch showing

used, ihe field notes describing the how a line may be laid oft

i ,. p ,-, • , i i i i at right angles to another

location ol these points should be at a point a.

complete and clear enough to make it easy for anyone to find the corners again at some future time.

PROBLEMS FOR PRACTICE

(In order to carry out the following problems it will be necessary to be provided with equipment consisting of tapes, pins, and range poles.)

1. With chain and range poles lay off a right angle.

Note. 3, 4, and 5 feet, or corresponding multiples of these distances, are sides of a right angle triangle. Give the theorem of geometry upon which this is based. (Fig. .7).

2. Measure the distance between two points a thousand feet or more apart and check with the results obtained by the instructor.

Random Lme_

True Line

Fig. 8. Sketch showing' method of locating points on a desired line between two points not visible from each other from a random line.

3. Let each student pace this or some other known distance and determine the length of his pace.

4. Estimate certain distances by pacing, and then measure accurately with a steel tape.

5. Chain over a hill between two points not visible from each other.

Range poles should be set at the points and then the chainmen with range poles should take such positions on each side of the hill as will enable each to see over the hill and past the other chainman to the range pole beyond. The chainmen then range each other in, making several trials.

6. Chain between two points when the view is obstructed by woods or other objects.

To accomplish this, run a trial or random straight line as near as possible to the distant point, leaving fixed points at known distances. Upon finding the error at the terminus, correct all other points into line a proportionate amount. Then the desired line may be chained.

7. Determine the distance to a visible but inaccessible object. Use two similar right-angled triangles. Fig. 9.

8. Prolong a line beyond an obstacle.

There are several ways to accomplish this, but the use of similar triangles is the only method suggested.

Let A B be points in the line to be prolonged beyond O, an obstacle. Make A B C a right-angled triangle. Prolong A C to F, making C F equal A C, and C E equal E F, and B C equal C D. Extend D E to I, making DG and G I equal to A C, also extend F G to H, making G II equal F G. Then H I are points in the extended line AB.

Fig-. 9. Sketch showing method of measuring to an inaccessible point.

Sketch showing method of extendf a line beyond an obstacle.

9. Make a survey of the lot on which the schoolhouse stands, locating buildings, etc.

10. Make a survey of the home farm or a part of it, as assigned by the instructor.

11. Make a survey of a lot or a field having an irregular side, by taking offsets at regular or irregular intervals, dividing the field into trapezoids. (See method of calculating areas of tracts with irregular sides) .

1 . How is a tract of land divided in making a chain survey?

2. What care should be taken in making field notes of a survey?

3. What care should be taken in marking permanent corners?

Chapter IV Map Making

Uses of a Map. When a survey of a farm or other tract of land has been made, a map should be drawn to show the location of the buildings, fences, lots, roads, and of the trees, streams, and other physical features of the land. A map enables the mind to grasp the facts in a way not possible with the field notes alone. Although not generally practiced, a good map of the farm can be used advantageously in directing the work of the farm. This map should also serve as the means of recording the location of drains and water pipes placed beneath the surface of the ground. If the fields are numbered and the map placed in the office or dining room of the home, it may be used as a basis in planning each day's work. The map will set also forth in a very forceful way any inconvenience in the arrangement of the buildings or fields.

The Final Map. The final map is made from the data recorded in the field book. As has been said, a sketch map usually forms a very helpful part of the field notes. The final map must be drawn carefully as well as accurately, and should be made as durable as possible.