The art of roadmaking, treating of the various problems and operations in the construction and maintenance of roads, streets, and pavements, written in non-technical language ... with an extensive bibliography and a descriptive list of reliable current books and pamphlets on these subjects

Front matter

BOUGHT WITH THE INCOME FROM THE

SAGE ENDOWMENT FUND

THE GIFT OF

Preface

RoADMAKiNG is an art, based on a science. Although it forms one of the most common and most important engineering works that engage the attention of man, the use of roads is so much a part of our daily life that we almost cease to consider their construction and upkeep as problems in engineering. Yet Roads may be said to be the backbone of the national life of a country and the most important element in the progress of civilization from the very earliest times.

This book is intended to give an outline of the history of road building; of the problems that confront the engineer in the location, construction and maintenance of roads; of the properties of the various road-making materials, and of many other features of the subject, and an effort has been made to present this information in a style suitable for the intelligent reader with or without previous technical experience.

No claim is made for originality in the contents, or for the presentation of new ideas or methods; in fact, since the days of Telford and Macadam little advance was made in the science of roadmaking, until the comparatively recent inventions of the modem mechanical methods of quarrying, stone crushing, grading, etc., and the various improved methods of dust prevention, street cleaning, and road maintenance. In the compilation of the material the columns of "Engineering News" and other technical periodicals have been drawn upon, government reports and a few trade pubhcations devoted to the making of roads have been freely quoted, and a large number of treatises have been referred to. Foremost among these may be mentioned Byrne's "Highway Construction," Baker's "Roads and Pavements," Tillson's "Pavements and Paving Materials," Aitkin's "Road Making and Maintenance," Judson's "City Roads and Pavements," and " Road Preservation and Dust Proven-

PREFACE vu

tion/' Soper's "Modern Methods of Street Cleaning/' Spalding's *' Roads and Pavements/' and Coane's "Australasian Roads."

The majority of these publications so specialize in one or more features of the subject^ or cover the entire subject in such encyclopedic detail, that they do not appeal to the average non-technical general reader. On the other hand, in spite, of the modern specialization of the engineering profession, even the most specialized engineer is often called on to make use' of information regarding some form of road work, and although he may be a specialist, and well informed on the subject of drainage, or of automobiles, he may be decidedly ignorant of the methods of roadbuilding and maintenance, which are outside of, but closely allied to, his specialty.

The present book has been written for both of these men. The object has been to condense into the comparatively small space of a single volume, the fundamental and essential principles of the roadmaker's art as presented by the most reliable authorities. It gives to the reader unacquainted with the subject a good general knowledge, and to the technical man, an outline of the main facts and an indication where further reliable and specialized information can be obtained.

To do this, all involved mathematical tables and formulas, records of tests and analyses, tables of statistics and the higher technical features of the subject have been omitted; information that covers pages in some treatises has been reduced to conclusions and tabulated, and such illustrations have been selected that will emphasize the popular features of the subject.

H. F.

220 Broadway, New Yokk, March, 1910

Contents

PAGE

PREFACE vi

POEM— "THE ROAD."— Anonymous xiv

INTRODUCTION: HISTORICAL SKETCH OF ROAD DE- VELOPMENT 1

Chapter I. Resistances To Traction

Object of a road — Causes of tractive resistance — Power required to move vehicles — Recent experiments in tractive resistance — Calculation of tractive force — Rolling friction — Effect of size of wheels — Effect of springs — General results of experiments in tractive resistance — Gradient — Loss of power on inclinations — Necessity of easy gradients — Hauling power of horses — Power of teams — Calculation of load on gradient — Load drawn by horses on grades — Steep grades objectionable — Methods of expressing grade ." 10

Chapter II. Road And Pavement Economics

Value of good roads — Advantages of paved city streets — Economic value of road improvements — Ultimate economy of road improvements — Questions affecting design of city pavements — Methods of payment for city pavements — Administration of highways — European systems of management — American systems— The labor-tax — Maintenance of city pavements — Opening of pavements 19

Chapter III. Principles Underlying The Selection Of Pavements For Different Purposes

Road and pavement definitions — Requirements of a good pavement— Properties of an ideal pavement — Relative values of qualities of different pavements — Use of tables in selection of pavements — Adaptability — Desirability — Serviceability — Comparative safety of pavements — Durability — Cost 28

CONTENTS ix

Chapter IV. Location Of Country Roads Page

Length of straight and curved roads — Comparative advantages of straight and curved roads — Economy the basis of location — Value of scientific road location — Methods employed in location — Characteristics of country noted — Instruments used — Contour lines — Topographical map — Levels and bench marks — Value of saving distance — Grades — Methods of overcoming grades — Determination of maximum grade — Most suitable maximum grades — Most advantageous grade — Establishment of maximum grade — Establishing the final grade — Curves — Curves on an ascent — Width of roadway — Selection of bridge sites — Principles to be observed in final selection — Method of final location 37

Chapter V. Construction And Protective Works

Earthwork: Classification of earthwork — Equalizing earthwork — Transverse balancing — Natural slope of embankments — Shrinkage of earthwork — Making embankments — Cost of earthwork . . 53

Foundations and Drainage: The importance of drainage — Systems of drainage — Object of side ditches — Surface drainage — Transverse contour 62

Highway Bridges: Location — Classification — Bridge trusses — Types of trusses and bridges — Short-span bridges — Low-truss bridges High-truss bridges — Plate-girder bridges — Use of timber in bridges — Masonry and concrete bridges — Culverts — Size of opening— Floorbeams and floors — Substructures — Abutments — Most economic bridge 69

Retaining Walls: Where retaining walls are built — Drainage — Sea

walls 87

Chapter VI. Materials Used In Road Construction

Most suitable material — Selection of material — Agencies causing destruction of roads — Physical agencies — Mechanical agencies — Chemical agencies — Organic agencies — Essential qualities of roadmaking stone — Hardness — Toughness — Durability — Cementing value — Classification of rocks — Igneous rocks^-Sedimentary rocks — Metamorphic rocks — Primary mineral constituents— Physical properties of rocks — Conclusions regarding paving stones — Principal varieties of roadmaking rocks — Granite — Basalt — Sandstone — Limestones — Sand and clay — Gravel — Free government tests 91

X CONTENTS

Chapter VII. Earth, Gravel, Sand, And Clay Roads Page

Earth Roads: The first step in construction — Preparation of roadbed— Preparation of road surface — Drainage — Culverts — Maintenance and repair 117

Gravel Roads: Gravel — First course — Second course 123

Sandy Roads: 126

Clay Roads: 126

Sand-clay Roads: Essentials to success — Causes of failure — Cost of

sand-clay construction 127

Bumt-clay Roads: Fuel — Preparation of the roadbed — Firing — Cost

of burnt-clay constrution 133

Tools Used in Construction of Country Roads: Tools for clearing and grubbing — Tools for grading — Scrapers — Road graders — Elevating grader — Carts — Dump-cars — Dump wagons — Surface

grader — Road leveler — Draining tools 137

The Earth-road Drag: Requisites for success — Description of drag — Object of road dragging — Theory of road dragging — Effect of dragging roads — Instructions for dragging — Conclusion 145

Chapter Viii— Broken-stone Roads

Difference between methods of Telford and Macadam — John Loudon Macadam — Thomas Telford — Tresaguet's method — Telford's method — Macadam's method — Modern telford and macadam — Defects of telford system — Defects of macadam system — Advantages and defects of broken-stone pavements — Difficulties in construction — Essentials for successful construction — Errors in construction — Materials — Dimensions of the macadam surface — Subgrade — First course — Second course — Third course — Trimming — RolUng — What holds macadam roads together — Steam rollers — Breaking stone — Stone crushers — Stone crushing plant — Stone distributing carts — Scarifiers — Straight-edge — Water carts — Cost of macadam surfaces 154

Chapter Ix— Roads In Mountainous Districts

Evolution of mountain roads — Grade — Importance of location — Object of drainage — Necessity for proper side slope — Width — Curves — Slide rock — Corduroy — Dressing 189

CHAPTER X. IMPROVEMENT AND MAINTENANCE OF COUNTRY ROADS Reconstruction and Improvement: Defects of existing roads

Benefits of improvements — Clay roads — Sand roads 203

CONTENTS XI

PAQE

Maintenance and Repairs; Necessity for maintenance — Systems of maintenance — Maintenance of country roads — Errors in maintenance — Cost of maintenance — Causes which make repairs necessary — Repair — Instructions to roadmen — Season for repairs ; . . . . 205

CHAPTER XL CONTROL AND PREVENTION OF ROAD

DUST

Importance of dust prevention — Value and effects of road dust — Effects of automobile traffic — Necessity for dust prevention — General results of experiments — Methods of dust prevention — Moisture — Salt water — Calcium chloride — Oil emulsions — Oils — Inexperience in handling road oils — General rules for oiling roads — Coal-tar preparations — Success of "tarviating" — Tar-spraying machines — Tests of coal-tar — Tar-macadam — Mixing tar-macadam— The " Gladwell" system — Use of tar-macadam in America — Rock asphalt macadam — Bitulithic pavement 218

CHAPTER XII. STATE AID LAWS Distribution of State-aid funds — Supervision of construction

Form of commission 248

Digest of State- Aid Laws:

State Highway Department — State Aid Highways — State Aid Fund — Powers and Duties of Counties — County or District Highway Engineers — How Localities get State Aid — Construction of State Aid Highways — Payment for State Aid Highways — Maintenance of State Aid Highways 252

Convict Labor on Roads 271

Excerpts from Specifications used in Constructing State-aid Roads in Massachusetts, New Jersey, New York, Connecticut, Pennsylvania and Maryland ." 272

Chapter XIII. The Design Of City Streets

Objects in planning city streets — Size of blocks — Location of streets — General plans for location of streets — Width of streets Area of streets — Width of pavement — Driving in middle of road destruetive — Center walks instead of sidewalks 296 xii CONTENTS

Chapter XIV. Stone Block Pavements Page

Roman roads — Cobblestone pavement — Belgian block pavement — Granite block pavement — Advantages and defects — Quality of the stone — Size and shape of the blocks — Manner of laying the blocks — Foundation — Laying the blocks — Joint fiUing — Pavements on steep grades — Durability of granite blocks 311

Chapter XV. Brick Pavements

Advantages and defects — Quality of brick — Brick-clay — Region of production — Manufacture of paving bricks — Size and shape of bricks — Testing bricks — Construction of pavement — Manner of laying bricks — Durability 323

Chapter XVI. Avood Block Pavements

Progress of wood paving — Woods used for paving — Qualities of treated wood pavement — Cost — Service — Durability — Tractive resistance — Quality of wood used for paving — Wood preserving methods — Creosoting — Impregnation of timber — Kreodone-creosote process — Creo-resinate process — Foundation and cushion — Blocks — Angle of courses — Expansion joints — Filler — Top dressing— Repairs and maintenance 335

Chapter XVII. Asphalt Pavements

Nomenclature — Bitumen — Asphalt — Historical — European and American pavements — Artificial sheet asphalt pavement — Durability ' 357

Construction of the Pavement: Foundation — Binder course — Composition of wearing surface — Mixing and spreading wearing surface — Failures of asphalt pavements — Repairs 365

Asphalt Block Pavement: Manufacture — Advantages and defects. . . 376

Coal-tar Pavements: Coal-tar and asphalt — Advantages — Defects. . . 377

Chapter XVIII. Concrete Pavements

Advantages of concrete — First cost — Cost of maintenance — Ease of traction — Foothold — Noiselessness — Cleanhness and healthfulness — Acceptability — Construction — Hassam pavement — Materials — Method of Work — Proportioning materials — Mixing— Topping and finishing — Road surface of concrete cubes — Concrete block trackway 380

Concrete Foundations 399

CONTENTS xui

Chapter XIX. The Cleaning And Sanitation Of City Page

Early history of street cleaning — Municipal growth in America — Uses of city streets — Sources of street dirt — Reasons for unclean streets — Aim of sanitation — Cooperation required — Varieties of city waste — Comparative cleanUness of pavements — - Orderlies — Machinery employed in street cleaning — Street cleaning authority — Organization of forces — Flushing — Disposal of street dirt — Removal of household refuse — Summary 401

Chapter XX. Sidewalks, Curbs, And Gutters

Width — Slope — Foundation — Requirements of a good walk — Materials used — Sandstone — Granite — Wood — Brick — Artificial stone — Gravel — Cement and concrete — Sub-foundation and drainage— Upheaval by tree roots — Foundation — Concrete base — Top Coat— Joints 424

Standard Specifications for Portland Cement Concrete Sidewalks of the

National Association of Cement Users 441

Curbs and Gutters: 444

Chapter XXI. Miscellaneous Roads And Pavements

Stone trackways — Steel trackways — Concrete-block trackways — Artificial granite blocks — Plank roads — Corduroy roads — Charcoal— Slag roads — Coal-slack roads — Clinkers — Destructor concrete— Shell roads — Cork — Copper slag — India rubber — Artificial paving stones — " Durax '' roads 450

Chapter XXII. The Roadside

Hedges and fences — Trees — Selection of trees — Planting — Tree-planting Association 463

Appendix

I. Specifications and Contracts 473

II. Pavement Guarantees 4S7

III. Concerning the Wear of Roads by Automobiles 491

IV. Statistics of American Roads 499

V. Bibliography of Roads, Streets, and Pavements 505

Index , 535

THE ROAD*

Soon as I knew you gathered from all lands,

And that my cause was in your skilful hands,

My pulses gave one throb and, with a bound,

To be with you I quitted all my ground,

City and village, forest, hill and plain.

And, Phryne at the judgment once again,

My veil of dust hiding the fears you gave me,

Behold me at your feet, my masters! Save, oh save me!

Oh save me, when I wander o'er the plains

Or, 'twixt the hedges of the country lanes,

I stretch my arms beneath some leafy glade,

Heavy with sleep and flecked with sun and shade;

When like a serpent undulate I glide,

Trailing my white robe up the mountain's side;

When, drunk with light, for breezes fresh I look

And wind along some chattering brook;

When I plunge into chasms, sound the deeps,

Or when above the mountains, near the skies,

I spread new worlds before men's dazzled eyes

For all the gifts on you I have bestowed,

Be my good doctor — save, oh save the Road!

My case is grave and needs swift remedy; Never has greater peril threatened me — True, as in France, so in all other climes. Much have I suffered from most ancient times. In days when, sometimes subject, sometimes free, People met people in fierce enmity, I bore the shock of many a battle train Rushing to doubtful death or doubtful gain; And, like some avalanche of myriad tons.

The murd'rous passage of the heavy guns.

* Translation of an anonymous poem recited by Mme. Bartet at the GaJa Performance given at the Com^die Francaise on Oct. 14, 1908, in honor of the First International Road Congress, Paris. Reprinted from "The First International Road Congress, Paris, 1908." By G. M. Harris and H. T. Wakelam.

xiv

THE ROAD XV

Chanting the Marseillaise, thirsting for war A nation shod with sabots passed me o'er, And the great Emperor, to spread his fame Over a world which trembled at his name, Compelled me to his will and, spurring fast, Triumphant o'er my prostrate body passed.

Glory I've borne — a heavy load to bear!

And others too as heavy and less fair; The clumsy cart, rumbling with jolt and jar Has crushed my bosom, leaving many a scar; Coach, post-chaise, and postilions in full cry, Flayed^my back sorely, as they galloped by.

The lumber wagon laid my sinews bare!

Yet I stood firm, defying wear and tear, Even I thought to breathe with greater ease; My toil, less burdensome, began to please.

No longer coach or post-chaise o'er me whirled, I was forgot, abandoned by the world.

Rarely some cart with tranquil pace would creep Me by, the lazy driver half asleep — Nought else by day or night disturbed my rest, Thus, by sweet dolce far niente blessed, Thinking my woes forever passed away, In a false calm I lived until one day —

A terrible monster burst into sight, God knows from out of what hell 'twas cast. Sheathed all in iron, a thing of might, Swiftly it passes — it has passed!

It has passed, with a fearsome hooting, Trail of smoke and a sudden glare, Like to some dazzling meteor shooting Over the highways of the air.

Fast and furious, onward dashing Tow'rds an horizon which e'er shrinks back; Fiery bolts of lightning flashing Over an echoing thunder track!

v

And ah! for me it means a wound indeed,

My face is crushed, my sides their binding bleed,

Car after car make ever fresh attacks,

Till my macadam's nought but ruts and cracks.

XVI THE KOAD

My body thus commences to decay And, into dust dissolving, floats away!

Must I then die?

No, no! For you are here; With you to aid me I have nought to fear.

Science and genius are in you alhed !

In your great wisdom I can well confide.

Quitting the beaten paths, you'll seek new ways Towards the cure for which your suppliant prays, Thresh out fresh doctrines, find the golden mean And, to preserve the route avoid routine!

Your patient's at your feet, apply your skill,

Probe, sound, investigate me as you will.

And, to prevent the tortures of the past.

Perfect a work, my masters, that will last!

Do this, and grateful evermore will be

All travelers — nay, all humanity;

For 'tis the road that is the fertile way,

Where Life and Progress must forever stray;

Where, seeking space and beauty far and wide,

The tourist flings unnumbered miles aside.

And over hills and valleys sows the seed

Which shall bring forth abundance in our need!

And when at length you have achieved your aim,

Restored my health and strengthened all my frame;

When by your work you've made me proof to shock,

Fearless, invulnerable, firm as rock;

My youth renewed, and more than ever fair,

I'll sing your praise here, there and everyv/here;

At every cross-roads I'll proclaim your glory

On Touring Club sign-posts for all to see!

The surest road to Immortality!

ADDENDA.

Page 23. It should be added to the last paragraph that some of the States have created and financed Highway Commissions, as is detailed on Page 252.

It should also be added that New York State has classified its roads as follows:

2,800 miles of main roads across the State from N. to S. and E. to W., known as " State " Roads, to be built and maintained at cost of State and by the State.

7,500 miles of main " County " roads, being the most important roads in the 47 Counties to be improved by the State, which pays 50%, the County paying 35% and the Town 15%.

70,000 miles of " Town " roads to be improved as eurth roads under State supervision, at the expense of the Towns, plus an equal sum to be donated by the State as *' State Aid."

Page 24. In reference to the last paragraph, while the Massachusetts State Highway Commission is one of the most important, at the present time the most important highway undertaking is probably that of the New York State Highway Commission, which is charged with the expenditure of the proceeds of fifty million dollars* worth of bonds, having taken from the State Engineering Department the charge of Highways in February, 1909.

Until about 1902 the Massachusetts Highway Commission was the most important State organization, the other States (including New York) learning much from the experience and good work in Massachusetts and meantime exceeding them in mileage. The mileage of New York was about 520 miles in 1909, while the Massachusetts Commission reports show their annual new mileage as: 47 miles finished in 1907, 38 miles built in 1908, and about 45 miles in 1909.

INTRODUCTION HISTORICAL SKETCH OF ROAD DEVELOPMENT*

The word "Road" (Anglo-Saxon radj a riding, and ridan, to ride) is commonly used to mean a public highway, but custom has applied it to any kind of a path open to foot or vehicular traffic. In the most ancient times there were no roads. The wants of man were few and were easily satisfied by nature and his knowledge and intercourse were limited to his immediate vicinity. But as the population of the various communities multiplied, and with it the necessities of life, man was led further afield to supply them. He formed rough pathways, which, in time, came to be the recognized routes from one locality to another, by means of which he satisfied his desire for investigation and intercourse with his neighbors, for the products of other localities, and for conquest.

''Countries inhabited by the least civilized people, whose wants can be supplied in the immediate vicinity of their dwellings, are almost destitute of roads; hence it has come to be said that roads are the physical symbol by which to measure the progress of any age or people. ' If the community is stagnant, the condition of the roads will indicate the fact; if they have no roads, they are savages.' " f

* The majority of current books on the subject of roads open with an introductory historical chapter, but the most comprehensive general histories may be found in Bj'^rne's "Treatise on Highway Construction," and Tillson's "Street Pavements and Paving Materials," and the best as applied to British Roads in Aitkin's "Road Making and Maintenance."

t Byrne: "Highway Construction."

Roads are not only the offspring of civilization, but they are also the greatest contributors to it and the greatest factors in its advancement.

Without them the arts that are so beneficial and necessary to the welfare of man could not develop; the interchange of ideas and the advantages that result therefrom could not be maintained; in fact, the civilization of to-day with its large cities and towns, its commerce, newspapers, and its highly developed moral, physical, and intellectual life, could not exist at all.

One of the very first steps in the opening up of a new country is the location and building of roads for the accommodation of travelers, the carriage of commodities, and for the development of the natural resources and manufactures of the country. Smiles, in his '^ Lives of the Engineers/' says: "The road is so necessary an instrument of social well-being, that in every new colony it is one of the first things thought of. . . . The new country, as well as the old, can only be effectually opened up, as the common phrase is, by roads, and until these are made it is virtually closed."

Of the early history of road building as' of other works done in the early life of the human race, little is known; while no authentic records exist, it is known that the importance of good roads was recognized in very ancient times. We are told by Herodotus of a stone roadway built by King Cheops about 4000 b.c, over which were conveyed the heavy materials for the construction of the great Eg5^ptian pyramid that bears his name. We are also told of a broad roadway connecting the ancient city of Memphis with the pyramids and lined on both sides with temples, mausoleums, porticos, monuments, etc. Later historians tell us of the pavements of Babylon, of many paved roadways diverging from that city and of a highway connecting Babylon and Memphis and passing through the great commercial cities of Nineveh, Palmyra, Damascus, Tyre, and Antioch. It is to the Carthegenians, however, that credit must be given for the earliest systematic and scientific efforts at road building, for as early as the fifth century B.C. they had developed a system of

INTRODUCTION 3

communication and military power that enabled them to maintain their integrity against Greece and the Roman Empire for four hundred years. The Romans learned the art of road building from the Carthagenians, and so fully did they appreciate the military advantages of improved highways that they soon became the greatest road builders of history.

The first Roman road of which we have historical evidence was built in 312 B.C. by Appius Claudius, the censor, and was named after him — the Appian Way. Some years later, the Flaminian Way was built, and under Augustus and Julius Csesar and succeeding emperors, Rome was made the center of a wonderful system of paved roadways stretching out to all parts of its great empire. These reached through Italy, Gaul, and Spain; through Germany, Hungary, Macedonia; to the islands of Sicily, Corsica, Sardinia, England, and to Africa and Asia Minor and the East; in all, a system of 372 roads, which, according to Antoninus, amount to a total length of 52,964 Roman miles.

It is said that for a distance of fifty miles from Rome many of these roads were decorated with temples and other superb edifices; lodging houses for the accommodation of couriers and mansions for soldiers were erected at regular intervals at the public expense. The width of these military roads was from 36 to 40 Roman feet, the middle portion being for the infantry, and the margins for horses and carriages. Many miles of these roads still remain as great monuments to the energy and skill of the Romans, and show the truth of the familiar saying that "All roads led to Rome.''

Not far behind the Romans in the art of road building were the ancient Incas of Peru, who built some thousands of miles of good roads in the face of great difficulties. In his "History of Peru," Prescott says of the mountain road from Quito to Cuzco: "It was conducted over sierras covered with snow; galleries were cut through the living rock; rivers were crossed by means of bridges swung suspended in the air; precipices were scaled by stairways hewn out of the native bed, and ravines of hideous depth were filled up with solid masonry." Most of this roadway was built at an elevation of 12,000 feet above the sea; it was more than 1500 miles long and 20 feet wide; paved with stones 10 feet square and had a running stream and a row of shade trees on each side.

After the decline of the Roman Empire, the roads fell into disuse and during the succeeding dark ages they were used more as aids to plunder and violence than for purposes of legitimate intercourse. Later they became practicable for pack horses and rude vehicles, but no effort was made to restore them until the middle of the eighteenth century when a revival of road building arose simultaneously in England and France. The highways of England at that time were wretched beyond description and an effort was made to improve this condition by the establishment of a system of turnpikes. Many thousands of miles of these roads were built, but they were little or no improvement over the old roads, and no further advance was made until the time of Macadam and Telford, to whom England is indebted for her present admirable system of roads.

In the United States the highways are much inferior to those of European countries, the reason for which Byrne * states may be attributed to (1) the excellence of the railroad systems and waterways; (2) the indifference of those in charge of highway maintenance; (3) the want of appreciation of the benefits of good roads and the fear of increased taxation on the part of the rural population; (4) the dispersion of the people over large areas in their search for desirable localities for residences, and (5) the ill-effects of the system requiring the personal services of the rural population on the highways.

The first inhabitants of this country were too fulty occupied in subduing the wilderness, establishing homes, opening farms to provide the necessaries of life, and setting up the framework of a government, to give much attention to the conveniences and comforts of transportation; and hence their wagon roads were of the crudest and poorest sort.

* "Highway Construction. "p. xxxviii.

i

CO

INTRODUCTION 5

Later, just as an extension of the population to the West necessitated the development of better means of transportation, the introduction of the railroad made less important the wagon roads and engrossed the attention of the population of the new territory. In a large part of the United States the railroad has been the pioneer and has rendered unnecessary long lines of wagon transportation. At present the country is so well supplied with excellently managed railroads that the chief function of the wagon road is to afford easy communication and transportation between neighboring farms, and between the farm and the nearest railroad station. Thus the problem of good roads had become a local question, both with respect to the community the road serves and to the materials and methods most suitable for use in the construction.

These facts relate to roads as distinguished from pavements, or road surfaces. The date of the introduction of pavements is very indefinite. In his "History of Inventions and Discoveries," John Beekmann, professor in the University of Gottingen, devotes a chapter to the paving of streets, and from his historical sketch the following more interesting points are taken:

"While Roman writers of early date often refer to paved highways and especially describe the famous Appian Way, of 3 1 2 B . c . , there is comparatively little reference to the paving of streets in cities. The streets of Thebes were regularly cleaned under the inspection of Telsarchs, and it is to be assumed that they were paved; and the Talmud says that the streets of Jerusalem were swept ever}' day, which undoubtedly implies a hard and solid pavement. There is no record of the first street pavement in Rome; but Livy mentions that certain streets were ordered to be paved in 169 B.C., and as early as 530 b.c. the Emperor Heliogabulus paved the streets around the palace with foreign marble. The streets of Pompeii and Herculaneum still show their paving blocks of lava, cut into deep ruts by the wheels of passing chariots.