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Chapter 1

This webpage reproduces a chapter of
The Transcontinental Railroad

John Debo Galloway

New York, 1950

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Chapter 3
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 p8  Chapter 2
The Origin and Development of Railroads Prior to 1870

The building of the Pacific Railroad marked the culmination of a movement that began in the years close to 1830, when the first railroad locomotives were brought to America. Not over a third of a century, hardly half the allotted three score and ten years of a man's life, elapsed from the opening of the first short section of the Baltimore and Ohio to the breaking of ground for the Central Pacific at Sacramento in 1863. In this brief time more than 30,000 miles of railroad were constructed in the United States. By 1870, over 52,000 miles of line had been built and placed in operation. Railroad building was one of the principal evidences of the rapid expansion of the American nation.

The first railroad in the world operated for general purposes was the Stockton and Darlington in northeastern England. Although projected in 1817 for transporting coal from the Wilton  p9 colliery near Darlington to tidewater below Stockton-on‑Tees, a distance of about thirty-eight miles, the necessary permission from Parliament was not obtained until 1821. George Stephenson made the surveys for the railroad and it was constructed under his direction. Stephenson strongly advocated the use of locomotives as being superior to animal power, and to convince the owners of the railroad he had them visit the Killingsworth tramway, where he operated his locomotives for their instruction. The Stockton and Darlington Railway was opened for traffic on September 27, 1825. The locomotive, No. 1, "The Locomotion," with Stephenson in control, drew a miscellaneous train of thirty-eight vehicles having a total gross load of ninety tons at a speed of twelve to fifteen miles per hour. The railroad proved a financial and mechanical success from the day of its opening.

The second railroad of importance in England was the Liverpool and Manchester. Projects for a tramway between these cities had been under consideration for years. In May, 1824, George Stephenson was appointed engineer, and after interminable delays in Parliament and other general opposition, the railroad, about thirty miles in length, was opened for traffic on September 15, 1830. The road involved much heavy construction, such as one long tunnel, deep rock cuts, masonry viaducts and bridges. It was laid directly across the country, for Stephenson felt that his rigid framed engines required a more or less straight track. The cost of the road is stated to have been $187,495 per mile, which in terms of modern monetary value would represent probably $500,000 per mile.

The power to be used in operating the line was the subject of much debate. Horses were suggested, but it was proved that they could not possibly handle the traffic. Another suggestion was that stationary engines be used, located a mile and a half apart and drawing cars by cables. This plan had many advocates. Finally a prize of 500 pounds sterling was offered and this brought forth four locomotives that were tested at Rainhall in  p10 October, 1829. After many trials, Stephenson's locomotive, the "Rocket," won the prize. The superiority of the locomotive over all other forms of power was so clearly demonstrated that the subject was considered settled. From that time on, there was a rush to build railroads all over England.

The First American Railroads

News of the success of railroads in England was not long in reaching America and in two cases, and probably others, Americans were sent to that country to investigate and to report upon what they saw. In December, 1824, there was organized the "Pennsylvania Society for the Promotion of Internal Improvements in the Commonwealth," and in 1825 the society sent William Strickland, an architect, to England to collect information on the subject of canals, railways, steam engines, and the industrial arts. In 1827 Horatio Allen, a young engineer, went to England to study railroads, and while there he executed a commission to purchase rolling stock and rails for an American railroad. Several English locomotives were purchased in the earlier years of railroad building.

By the time the first railroads were projected, many men had become aware of the limitations of canals. It was clear that railroads paralleling the Atlantic Ocean were unnecessary. What was required was a means of traffic between the cities on the coast and the great interior beyond the Appalachian Mountains, which was rapidly filling which settlers. To a limited extent, rivers and steamboats supplied an answer, but they could not cross the mountains. Charleston in South Carolina, Baltimore, Philadelphia, New York, and to some extent Boston, required a cheap, quick, dependable transportation link between the two sections of the country. New York had solved the problem in a partial manner by building the Erie Canal to Buffalo, opened in 1825. The canal gave New York a preeminence that the city has never lost. The Chesapeake and Ohio Canal, designed to connect tidewater with the Ohio River,  p11 never crossed the mountains. Further means of transportation was needed.

The Baltimore and Ohio Railroad

A number of railroads were projected in 1828, 1829, and 1830, but by general consent the Baltimore and Ohio Railroad is acknowledged as the first to organize and build a line for general traffic. That railroad, long ago grown to be one great systems of the country, is the only one to retain the original name and to preserve its corporate existence throughout a history of well over a hundred years. On the evening of February 2, 1827, a number of Baltimore merchants met at the home of one of their members and launched the projected. Incorporation followed, and Virginia and Pennsylvania soon confirmed the charter.

To mark the beginning of construction, a cornerstone was laid in Baltimore on the Fourth of July, 1828, the event being signalized by the presence of Charles Carroll of Carrollton, the last survivor of the brave group of men who assembled at Philadelphia and signed the Declaration of American Independence, fifty-two years before.

After the usual difficulties of financing had been overcome, and in spite of the opposition of Congress, which was supporting the canal, and in opposition to the general public, the road was complete to Ellicotts Mills, thirteen miles from Baltimore. It was put in operation in May, 1830, with horses as its motive power. Operation by horses did not last long, however, since the small experimental locomotive, "Tom Thumb," was successfully run to Ellicotts Mills, on August 28, 1830. The road was extended to Point of Rocks on the Potomac River, seventy-two miles from Baltimore, and opened for traffic April 1, 1832. Disputes with the Chesapeake and Ohio Canal were compromised and on December 1, 1834, the road reached Harpers Ferry. A branch to Washington from Baltimore was opened August 25, 1835. Cumberland, on the Potomac, 178 miles from  p12 Baltimore, was reached November 5, 1842, after many difficulties, mostly financial. The extension to the Ohio River at Wheeling was a difficult piece of work, involving eleven tunnels, thirteen bridges, and a switchback across the mountains while a long tunnel was under construction at an elevation of 2,620 feet above sea level. Wheeling was reached January 1, 1853. An extension to Parkersburg on the Ohio was opened May 1, 1857, and by connections with other roads across Ohio, Indiana, and Illinois, St. Louis was reached in the same year. There was then a continuous line west from Baltimore that required only five changes of cars and two short steamboat trips.

The South Carolina Railroad

At practically the same time that the Baltimore and Ohio was projected, a railroad from Charleston to the Savannah River opposite Augusta, about 136 miles, was chartered by the South Carolina legislature on May 12, 1828. Although chartered under the name South Carolina Canal and Railroad Company, the line was generally known as the Charleston and Hamburg. By January 1, 1830, six miles of the road were in operation. When the railroad was completed to Aiken in 1833, it was the longest railroad in the world. The chief engineer was Horatio Allen, who had worked as an engineer on the Delaware and Hudson Canal, and while in England had examined a number of the coal tramways operated by stationary engines and by locomotives. He had also visited the Stockton and Darlington Railway and had seen the operation of the line by horses and by locomotives. Employed by the Charleston and Hamburg he strongly recommended steam power. A locomotive, the "Best Friend of Charleston," was built in New York and placed in regular service on January 15, 1831.​a1 A second locomotive designed by Allen, went into service March 31, 1831. The Charleston and Hamburg Railroad was a financial and mechanical success, and continues today under other names as a part of the Southern Railway System.

Progress of Railroad Building up to 1880

While the railroad work done in England preceded that in America and had influenced train and track design, it was not long before the Americans had originated and made use of railroading practices more adapted to the new country they were to serve.

The success of the first projects soon opened men's minds to the value of this new means of transportation, which far surpassed canals. Railroads not only could cross mountains and could be operated at all seasons, but they cost less than canals, and traffic was moved at far greater speed on them than on canals. However, the first canals generally moved bulk freight very cheaply and their investments paid a greater rate of interest than did those of the railroads.

The country grew rapidly in population and in area, and railroad building kept pace with the westward movement.​b The following table illustrates this growth.





1830 12,866,020 23
1840 17,069,453 2,818 2,795
1850 23,191,876 9,021 6,203
1860 31,443,321 30,626 21,605
1870 38,558,371 52,922 22,296
1880 50,155,783 93,267 40,345

The growth in mileage in the several decades is interesting when different sections of the country are considered. In 1850 there was no direct line from New York to Boston. Construction was only beginning in the southern states, notwithstanding the fact that one of the first railroads had been built by South Carolina. In the 1850‑1860 decade many lines were built in the South connecting the principal centers, and 30 per cent of the railroads were in that section. The largest growth, however, was in the North, especially in Ohio, Indiana, and Illinois. Those three states accounted for one third of the mileage built in that  p14 decade. In spite of the Civil War, when so many railroads were destroyed in the South, the construction of railroads continued in the 1860‑1870 decade, and it was during this period that the Pacific Railroad was built.

In the West, Chicago had become central point from which railroads radiated. In 1850 that city, which had a population of 23,722, had one short road. By 1860 the city had grown to a population of 109,260, and several lines went out from it. St. Louis was an early competitor of Chicago, but when the time came in 1863 for President Lincoln to designate the terminus of the Pacific Railroad, there was no questioning his wisdom in selecting Omaha and Council Bluffs, because those towns were situated on the direct line from Chicago to the Pacific coast. Of the roads extending westward from Chicago, the Rock Island reached the Mississippi River in 1854, and shortly after it was followed by the Galena and Chicago Union Railroad, afterward the Chicago and North Western. In 1855 the Chicago and Alton, and in 1856 the Chicago, Burlington and Quincy reached the Mississippi River. Near St. Louis, the Hannibal and St. Joseph reached the Missouri River in 1859.

Up to 1860, railroad building was carried out by numerous scattered companies. When public resistance had been overcome, there was a rush to build railroads everywhere in the country. Short lines were projected between any two points, although many were never built. There was little or no preconceived plan for the numerous lines, and since the financial resources of many of the projectors were limited and their knowledge of costs pitiably inadequate, the results were often receiver­ships and foreclosures in which the original stockholders lost their money. After the Civil War, in the decade 1870‑1880, numbers of independent lines were united to form single systems in the several sections of the country. This process of amalgamation went on in the years that followed. An early example of this was in 1853, when the New York Central was formed by a combination of eleven companies; by 1858 five other lines had  p15 been added. Later followed the union of the Hudson River road, the Harlem, the Lake Shore, the Canada Southern, the Michigan Central, and others, thus making a system of 4,000 miles of line.​c

The variety of systems and independent lines is indicated by one of the major troop movements during the Civil War. It had become necessary to send some 20,000 troops from the Army of the Potomac to General Indicates a West Point graduate and gives his Class.Rosecrans near Chickamauga. After considerable discussion it was decided to move the troops by rail, President Lincoln making the final decision. Estimates of the time required varied from fifteen days to three months. Railroad officials took charge of the movement, the principal one being from the Baltimore and Ohio. The troops entrained in Virginia, passed through Washington and thence by the Baltimore and Ohio to Wheeling, crossed the Ohio River on a ferry, and again entered cars to Bellaire. The route then lay across Ohio and Indiana to Indianapolis, where the troops marched across the city to another railroad, by which they again reached the Ohio River. They crossed the river on a pontoon bridge made of barges and by another railroad reached Chattanooga. The first troops arrived in seven days, and by eleven days the movement of 20,000 men over a distance of 1,000 miles had been completed. Several railroads and two crossings of the Ohio River by ferries or boats were required, and it was only by the close cooperation of the managements of several lines that it was made a success.​d

State Railroads

There were ambitious politicians in that early period, so it was not surprising that seven states went into the business of building railroads: Pennsylvania, Massachusetts, North Carolina, Georgia, Indiana, Michigan, and Illinois. Michigan tried the experiment after the panic of 1837, and after going into debt over $5,000,000, sold out at a loss. The effort of Illinois in that direction was one long series of misdirected endeavors, characterized  p16 by political incompetence, mismanagement, and corruption. In the end, all the state roads were sold, bringing a heavy loss to the taxpayers. This result could have been foreseen by investigating the failure of most of the canals that had been built, projects that had earlier nearly bankrupted the states that entered into them.

Evolution of Railroad Design

At the period when the Pacific Railroad was built, railroad design was still in a state of transition. However, many, if not all, of the essential elements had already been developed — track, bridges, rolling stock, telegraph, construction, and repair shops and terminals. The important executive and operating forces had been brought into being. But, many changes were taking place, and larger and more efficient equipment was being manufactured and used. It can be said, with equal truth, that similar changes are still taking place.


It is a truism that the track of a railroad as a part of the physical plant is the one thing upon which everything else depends. In the early tramroads and on many of the early railroads, the rails were made of timber, often supported on stone blocks embedded in the earth or resting upon wooden ties. The rails were usually of pine, upon which was fastened a strip of hardwood or, in later practice, a strip of flat iron as a running surface. Such rails were not of great strength and were subject to rapid decay and excessive wear.​e George Stephenson's first locomotive upon the Killingworth coal tramway in 1814 ran on cast-iron rails made in sections three feet long.

When the Camden and Amboy Railroad was started in 1830, Engineer Robert L. Stevens advocated the use of all-iron rails in place of wooden rails with the strap iron surface. Stevens went to England to order rails, and on the way devised the "T" rail in substantially the same form that has been used since that  p17 time. In form and proportion, the Stevens rail may be seen on any track today.

Stevens also devised the hook-headed spike for fastening the rail to the wooden ties, a form of fastening that is still employed on American roads. He connected the rails together at the ends by what he called an "iron tongue," which has developed into the fishplate or angle-bar construction of the present day.

It was not long before the costly method of supporting the rails upon stone blocks was abandoned in favor of the wooden tie. The blocks could not keep the gauge true, and what was more important, the blocks gave a support that was too rigid. Therefore the wooden tie of dimensions similar to those now in use, became standard, for it was found that it provided a track bed over which locomotives and cars rode with greater ease and security.

Early railroads were bedeviled by the different gauges adopted on different lines. In England, Stephenson had adopted a gauge of four feet eight and one half inches, following the practice of the coal tramways, which probably were made the width of the wheels of an ordinary wagon.​f In America there was a variety of six or more gauges, ranging from three feet up to six feet. Horatio Allen advocated a gauge of five feet and it is to be regretted that his advice was not taken, for the extra width over the now standard gauge of four feet eight and one half inches would have been much better for the heavy rolling stock of modern times. However, the English gauge prevailed, and other American gauges were changed to that standard, with some 12,000 miles altered in the South alone in 1886.

For forty years or more wrought-iron was use for rails, the length gradually increasing from fifteen feet to thirty feet, and the weight up to fifty or sixty pounds per yard. The first iron rails were imported from England, but in October, 1845, iron "T" rails were rolled at the Montour Rolling Mills in Danville, Pennsylvania. When steel rails first came into use, they were imported from England, but the cost was almost prohibitive  p18 until Bessemer in 1855 introduced his process for manufacturing steel rails. After that the use of steel became general. The first steel rails rolled in America came from the Chicago Rolling Mills in 1865. Steel rails were first used on the Pennsylvania Railroad in 1865, but iron rails were used throughout the entire length of the Pacific Railroad.


The development of the modern American locomotive brought on a corresponding development in track. In fact, the increasing weight of locomotives forced the development of a proper track.

Long before locomotives were invented, James Watt had perfected the steam engine, and in 1775 the British firm of Boulton and Watt began the manufacture of engines at their Soho Works near Birmingham. A number of names, French and English, are connected with the early use of steam, and years before Watt was born Newcomen engines were operating pumps at a number of Welsh mines. However, the many improvements made in the steam engine by Watt transformed it from a crude, inefficient, and wasteful machine into the one we know today.

When Stephenson built the "Rocket" that won the prize at Rainhall in 1829, he abandoned all the complex gear of the previous locomotives and placed two cylinders in an inclined position on each side of the boiler, each connected to a single pair of driving wheels. The cross heads of the pistons were connected directly by a rod to the crank on the outside of the wheels. Stephenson also invented the device for directing the exhaust steam from the cylinders up the smoke flue, which greatly increased the draft across the fire. He used a boiler with fire tubes and provided a tender that weighed four and a half tons.

Meanwhile, the subject of locomotives was actively considered in America in connection with the new railroads. When in England in 1828, Horatio Allen purchased one locomotive, the  p19 "American"º from Stephenson and Company. It arrived in New York in January, 1829. Allen also bought three locomotives from Foster, Renwick and Company of Stourbridge, England. The first to arrive, the "Stourbridge Lion," reached this country in May, 1829. When Allen gave a trial trip August 8, 1829, on a road with wooden and strap iron rails, the engine operated successfully. However, it was later discarded as being too heavy for the track. The "America"º had two pairs of driving wheels that were directly connected to the two cylinders placed in an inclined position, somewhat similar to the "Rocket." The "Stourbridge Lion" was the "grasshopper type," the cylinders being vertical and operating a type of walking beam fixed at one end. Vertical rods fastened to the other end of the walking beam connected to the rear pair of driving wheels.

The cost and delay incident to the importation of locomotives from England eventually led to the building of locomotives in America. The year 1830 is notable for the introduction of two American-built locomotives. On the Baltimore and Ohio, Peter Cooper tried out the "Tom Thumb," which was a success, in spite of failing in a contest with a horse. The boiler of the "Tom Thumb" was vertical and provided with tubes made of gun barrels, and a blower was used to keep up steam. The other locomotive built that year was the "Best Friend of Charleston,"​a2 designed by E. L. Miller and C. E. Detmold. Its boiler was vertical but the two cylinders were nearly horizontal and were connected to cranks on the axle of one pair of the two pairs of driving wheels.

From the very beginning, improvements in American locomotive building were rapid. Locomotives increased in weight and power and new devices were constantly being added. Among these may be mentioned the reversing gear, the cab for engine driver and fireman, the steam whistle, the headlight, the bell, the equalizing levers and springs, engine brakes, and a multitude of other accessories. By 1860‑1870, locomotives weighing forty to fifty tons, having eight driving wheels and burning  p20 either wood or coal, were available. In thirty years a new and powerful machine had been brought into existence in response to a pressing need.


At the same time that the development of the locomotive was taking place there was a corresponding evolution of railroad cars, both for passengers and freight. The first railroads were projected as carriers of freight, but the demand for passenger transportation rapidly increased and cars were accordingly designed for people who wanted to travel.

On the first railroads, horse-drawn passenger cars were made with a boxlike enclosure resting on four wheels and without springs. Two long seats were provided on each side. When it became necessary to build cars to be drawn by a locomotive, stagecoach bodies, which were available, were used, each coach being mounted upon four wheels. This type persisted in Europe, but American builders soon developed the long car with a center aisle and seats placed at right angles thereto. In 1834, Ross Winans constructed a car, the "Columbus," mounted on four bogie trucks at each end and large enough to accommodate sixty passengers, some seated on top of the car. By 1840 passenger cars measured thirty-five to forty feet in length with a width of eight feet and a height of six feet six inches. The seats were narrow and the ventilation bad, and the heating was provided by a stove at each end. By 1870, when the Pacific Railroad was in operation, passenger cars were of the same pattern, but larger, and it was only in later years that more comfortable coaches were provided.

The greatest improvement in passenger cars was made when George M. Pullman perfected the sleeping car. The increasing length of railroad lines resulted in night travel, and as early as 1836 crude sleeping cars with tiers of bunks were built to accommodate it. Pullman placed his first real sleeping car, the "Pioneer," in operation in 1865. The "Pioneer" was made one  p21 foot wider than the ordinary cars and there was a raised portion of the roof arranged with ventilators. George Godfrey Leland, in a letter dated October 31, 1866, describes an early Pullman car in the following excited terms:

"A remarkable subject of interest, which our party examined this morning, was the City of Chicago — not the metropolis itself, but its reflection, as regards splendor and enterprise, in a 'sleeping car' of that name, which runs on the 'Illinois Central.' This car cost twenty thousand dollars, and is said to be cheap at the price. Every comfort which can be placed in such a vehicle is to be found between its wooden walls. The seats, the sides of the car and the ceiling are exquisitely adorned in marquetrie or inlaid woods, while the gilded glass frames, in ormolu, and the general tone of color, are truly artistic. It is heated by a separate furnace beneath, and its lounges and mirrors, with every other luxury, make it in fact a rolling palace. Not less remarkable is the corresponding seat-car for day passengers which surpasses in splendor, and still more in comfort, any car which I have even seen on an Eastern road. There is yet another car, which cost thirty thousand dollars, which I did not see, but which is described as a miracle of its kind. Luxury and enterprise are advancing with rapid steps in the West. It is said that the most costly diamonds, the richest laces, and the finest cashmeres sold in Broadway or Chestnut streets, find their way, for the most part, to these ultra-montane towns. Perhaps in this rapid action of expenditure, as well as acquisition, we may find one of the leading causes of the active growth of every industrial interest in the West."

The Pacific Railroad had passenger cars for the use of poor people that were anything but splendid. They were arranged somewhat like Pullman sleepers. The seats faced each other in pairs and the passengers sat on a frame of wooden slats. At night the slat seat could be drawn out to form a bed. The traveler provided his own straw mattress and blankets, if he had any. In 1885, the author traveled from Sacramento to Ogden in one  p22 of those "emigrant" cars attached to a freight train, a trip that took three nights and three days.

The evolution of freight cars went forward at the same time as that of passenger cars. The trucks and supporting frame were and still are substantially the same in both types. The various car bodies, flat, box, or open, were built at an early date to accommodate the several kinds of freight. Brakes on the wheels were operated from the end platforms or the roof of box cars. One important part of a train is the connection between the cars that transmits the pull of the locomotive to the following cars. At first this connection was by a chain, an unsatisfactory device because of the violent jerks and bumps given the train by the locomotive. Chains were replaced later by a draft gear arranged with springs, but for a long time afterward the coupling was made with an iron link and pin. It was not until the decade of the 1880's that the automatic coupler came into use.

Train Operation

In England the railroads were built double-tracked, and operation of the trains by schedule was not difficult. But in America, owing to the long distances traversed by the railroads and the undeveloped state of the country, it was necessary to utilize the single-track line, with passing tracks being provided at stations. In the beginning, train operation was by schedules with designated points where trains should pass; but if one train was delayed, the entire system was thrown into confusion. A number of devices were therefore introduced, some of which depended upon the locomotive driver seeing distant signals. It was not until after the perfection of the telegraph by Samuel F. B. Morse that the problem was solved. In 1851 the telegraph was first used by the Erie Railroad to direct train movements.


In the beginning, American railroad engineers patterned their bridges after construction that had been followed for highway traffic through the preceding ages. Stone arches had been  p23 used by Roman builders and the remains of their bridges formed the models from which modern stone arches had been built. The Romans had also built timber and pile bridges, types which were in common use long before the advent of railroads. The first iron bridges had been constructed in England at Coalbrookdale, where a cast-iron arch highway bridge was erected in 1776.

The first railroads in England were built on a very expensive plan compared with American railroads. In America, both on highways and on the railroads, it was recognized that inexpensive structures were essential. Therefore wood was used freely in developing various types of timber and metal bridges that answered the purpose and were economical. It was soon seen that it was not necessary to build permanent structures for the first railroads. A wiser plan was to build structures that would serve for a time and then be replaced later. One reason for this point of view was the rapid increase in weight of the locomotives and other rolling stock. Heavier loads required that older structures be replaced long before they wore out.

Before 1847, the art of bridge building was empirical, as no theory of the relation of the stress in bridge members to the loads imposed by a railroad train had been developed. The work was largely in the hands of intelligent carpenters who fashioned their structures in accordance with their judgment. It was in 1847 that Squire Whipple of Utica, New York, published a work on bridge building in which he set forth the essential principles of bridge design, and from that time on the design of bridges was based on a mathematical treatment of the relation of loads to the stresses and the strength of the materials used.

The names of a number of the early bridge builders are attached to the forms of trusses that they originated. The truss most used in early wooden bridges was that patented in 1840 by William Howe. In the Howe truss the vertical members are of iron or steel, and all the other members, chords and diagonals,  p24 are of timber. In any other truss some of the members are subjected to compressive stresses and some to tensile stresses. The chief difficulty lies in connecting the pieces of timber together to take the tensile stresses. Wood is also subject to decay. However, the Howe truss, or its modification, the Burr truss, was for many years the best form of bridge truss in the United States. Up to the time the Pacific Railroad was built, the wooden Howe truss bridge was the standard for railroad bridges.

Iron bridges also were built to a limited extent. One was used on the Philadelphia and Reading Railroad in 1845, and in 1846 some were installed on the Baltimore and Ohio. When that road was extended from Wheeling, the chief engineer, Benjamin Latrobe, installed several Bolman iron bridges. The use of iron bridges slowly made its way, but at the time of the building of the Pacific Railroad they had been used only on some of the older railroads.

When the Mississippi River was reached by the railroads, the engineers were confronted with crossing the largest river in the country. A bridge over the Mississippi was built in 1855 by the Chicago and Rock Island Railroad at Davenport and was the first of a number built on the upper reaches of that great stream. It was not until the seventies that the design and construction of large bridges took on its present character.

Pile trestles were used for many of the crossings of ordinary streams. For crossing deep ravines, trestles were made of framed timber, resting upon piles or sills placed directly on the ground. Each set of piling or of framed trestle, called bents, was built about sixteen feet apart and the space between was spanned by wooden girders upon which the railroad ties were fastened to support the rails.

In the openings where an earth fill was used, the stream, usually of moderate size, was passed through the fill by a culvert. Such culverts were sometimes built of timber, with sufficient clearance to permit the building of a more permanent masonry arched structure at a later date.

 p25  Location

The evolution of railroads quickly brought into being a group of engineers who learned and developed the science of railroad location in the school of experience. Among these pioneer railroad engineers were Benjamin H. Latrobe, John B. Jervis, Horatio Allen, Robert L. Stevens, and George Lowe Reid.

The early general belief that a locomotive could not ascend a grade was quickly dissipated. However, it was understood that the rate of grade was an important factor in fixing the number of cars a locomotive could haul. Grades of 2 per cent, 106 feet per mile, were recognized as a reasonable maximum that was rarely exceeded except on the steepest lines in the mountains.

The straight sections of the lines, called tangents, were joined by circular curves of different radii, but it was soon found that sharp, short-radius curves offered much resistance to the passage of the train. Experience indicated that curves of ten degrees (radius 574 feet), were as sharp as should be used, except in rare cases. Where the topography permitted, curves of larger radius would be used.

Normally, a railroad should be located as close to a straight line as possible and with a level grade. On the open plains of the Mississippi Valley this was often possible. However, the location generally followed the valley of a river or creek, where the stream course was favorable. The location of the Union Pacific from Omaha directly to the west illustrated this principle. The line followed the valley of the Platte River and its tributary, Lodgepole Creek, for nearly 500 miles. By following the stream, the hills or rolling plains, cut by tributary drainage, were avoided.

However, it is not always true that a stream should be followed, particularly in the case of rivers that have their source in high mountains. In the Sierra Nevada, the rivers, rising in the highest part of the range, have a steep descent into canyons  p26 they have cut to depths of 3,000 feet or more. A railroad following such a river would eventually wind up at the bottom of a deep canyon. It is to the eternal credit of Theodore D. Judah that in the location of the Central Pacific Railroad across the Sierra Nevada, with an elevation of over 7,000 feet, he carefully avoided streams and placed the line on a ridge between two rivers. General Dodge followed the same plan when, in climbing the Rocky Mountains, he turned from Lodgepole Creek and followed a ridge near Crow Creek past Cheyenne up to the Sherman Summit at Evans Pass in the Black Hills, now called the Laramie Mountains, at an elevation of 8,262 feet.

Thayer's Notes:

a1 a2 The Best Friend was not in "regular service" very long. An interesting and amusing account of its first run, and of its spectacular end, is given by Waugh, West Point: The Story Of The United States Military Academy. . ., pp95‑96.

b A good general history of the progress of the railroads in the United States is onsite: John Moody's Railroad Builders.

c A good history of the New York Central, detailing the process of amalgamation, is onsite: Alvin Harlow's The Road of the Century.

d For further detail on this first mass transport of troops, see "United States Military Railroads, 1862‑1865" (JAMHF 2:70‑89).

e Strap rails were also very dangerous: see Harlow, op. cit., p12 (and my note there).

f I hope, gentle reader, that you are not one of those who know that what is now the standard U. S. rail gauge derives from the axle width of a Roman war chariot. This old canard, not even the most intelligent of such fabrications, has been debunked so completely at both ends, by both railroad experts and classicists, that I would not mention it were it not for the many instances of the statement parroted across hundreds of webpages. At any rate, it is simply not true: see the excellent page at Snopes; which fails, however, to note that to top it off, there was no such thing as a "Roman war chariot": the Romans did not use chariots in warfare.

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Page updated: 20 Feb 14