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ill effects it may cause besides the additions to the statical stresses that must accompany it. It depends on the manner of application of the loads as well as on the character of the bridge. Its importance has been recognized ever since iron bridges have been built, but definite experimental information is very scanty, and Professor Robinson's paper referred to by Mr. Lindenthal is a most valuable contribution to our knowledge of the subject. Now of course Mr. Lindenthal knows all this as well as the author, but the latter thinks the indictment against cantilevers is too sweeping, because he does not in his remarks sufficiently distinguish between the statical deflection to which they are undoubtedly more liable than other types, and the dynamical deflection which may or may not accompany it to a dangerous degree. It does not follow because a particular cantilever bridge is subject to violent oscillations that the fault is inherent in the system. There are other cantilever bridges that are as steady as any truss bridges The relative amounts of dead and live load are important factors as Mr. Lindenthal says, as also the higher or lower stress per square inch allowed in the members, the general design whether tending to extreme lightness or otherwise, and other circumstances that vary from bridge to bridge. In Mr. Lindenthal's main contention however, that where a cantilever is likely to give an unstable springy bridge, it is for most purposes objectionable, most engineers will agree with him, and his warning against the neglect of rigidity and durability is perhaps more necessary in America than in Europe. In England our errors are generally regarded as lying rather in the opposite direction.

Mr. Lindenthal's description of his moment-girder, as he calls it, is most interesting and, to the author at least, new. It has obviously great merits, but one's first impression is rather to shrink from making the security of a bridge depend on a mechanical device which will require periodical attention. His reference to expansion rollers is scarcely a happy analogy, because if all the bridges provided with that luxury were dependent for safety on the rollers doing their duty, there would be a great many more bridge failures than there are. However, Mr. Lindenthal has, no doubt, a complete answer to this prima facie objection which he must have fully considered.

Mr. Whited's observations on the unwisdom of rivetting a straight and curved bar together, under the expectation of a fair division of stress between them, are very just but the writer can scarcely imagine any engineer adopting such a course. There is nothing in the Sukkur Bridge which he quotes, designed in that way, all the main members of that structure, so far as the writer knows, being symmetrical in form.

Thursday, 14th February,

F. R. F. BROWN, Member of Council, in the Chair.

The following having been balloted for were duly elected as

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By T. T. VERNON SMITH, M. CAN. Soc. C. E.

A series of railway articles, have recently appeared, in a leading magazine, which have been decidedly interesting and deservedly popular, but they contain a number of statements which, designed to please American readers, are by no means correct in fact or generous to the engineers of other nationalities. Old country engineers have learned to regard railways and the locomotive, especially in its present form, as their undisputed invention and introduction, and although they are not so inconsiderate as to claim every individual improvement, yet they consider that in this one department of engineering, the great

bulk of the evolution of the present railway has been peculiarly British, and that Americans have not contributed a great deal towards the mechanical and scientific triumph that we now see. The first number of these papers is particularly guilty and ungracious in claiming for American inventors everything valuable and important that has been found out. "The modern railway," "was created by the Stephensons in 1830, when they built the locomotive Rocket. The development of the railway since is due to the development of the locomotive." "The earlier locomotives of this country modelled after the Rocket, weighed five or six tons, and could draw on a level about 40 tons. After the American improvements, which we shall describe, were made, our engines weighed 25 tons, and could draw on a level some sixty loaded cars, weighing 1,200 tons. The Stephenson type once fixed has remained unchanged (in Europe), except in detail, to the present day." "When we come to the United States we find an entirely different state of things. The key to the evolution of the American railway is the contempt for authority displayed by our engineers, and the untrammelled way in which they invented and applied whatever they thought would answer the best purpose, regardless of precedent." "When we began to build our railways in 1831, we followed English patterns for a short time, but our engineers soon saw that unless vital changes were made, our money would not hold out, and necessity truly became the mother of invention. The first and most far-seeing invention was that of the swivelling truck, which enables the engine to run round curves of almost any radius. This enabled us to build much less expensive lines than those in England, for we could avoid hills and other obstacles. The swivelling truck was first suggested by Horatio Allen for the South Carolina Railway in 1831, but the first practical use of it was made upon the Mohawk and Hudson Railroad in the same year. It is said to have been invented by John B. Jervis, Chief Engineer of that road. The next improvement was the equalizing beams or levers, by which the weight of the engine is always borne by three out of four or more driving wheels. The original imported English locomotives could not be kept on the rails of rough tracks." "Another American invention is the switch-back, by which the length of line required to ease the gradient is obtained by running backwards and forwards in a zigzag course, instead of going straight up the mountain. This device was first used amongst the hills of Pennsylvania over 40 years ago, to lower cars down into the Nesquehoning Valley." Now this is sufficient to shew the general style of

claiming everything that has led up to the present development of railways for American engineers only. Excepting to the Stephensons, not one particle of credit is hinted at as belonging to anyone else. Touching however the American invention of the switch-back, Mr. Curtis Clarke's claim of 40 years' use in Pennsylvania is not sufficient. In Tom Moore's Epicurean, written in 1800, a good 40 years before that again, is a capital description of the switchback, and by it the pretty priestess of the Egyptian temple saves the life of her lover. Tom Moore wrote some of his finest poetry, including Lalla Rookh and the Epicurean, in the heart of the lead mining district of Derbyshire, where the "switch-back " has been in use for a century, as a means of bringing the materials to the smelting works in the valleys. All that American engineers invented in this contrivance was the name, and as for some of the other claims that are inferentially supposed to have evolved the American locomotive and railway from the primitive rudeness of the English original, it may prove that the improvements rest upon an equally poor foundation.

In comparing English and American practice, especially in the earlier days of railways, one great source of confusion and mistake, made by American authors, arises from the fact that in England there have always been two distinct classes of railway, one chartered by Act of Parliament the affairs canvassed and discussed every half year, and all their peculiarities and inventions thoroughly ventilated by the papers and in other ways, whilst the others are strictly private, their proceedings, experi. ments and practices utterly unknown to the public, and but seldom finding their way into the public press. Yet these "private" railways preceded the public lines by years; until quite recently even their mileage was in excess of the public lines, and almost every important invention that has led to the result of the modern locomotive and the existing railway was invented, tested and developed on the private railways of Great Britain years before there was a mile of railway in America. The double trucked car for instance, which in the magazine is claimed as the invention of Ross Winans, was in use for carrying timber and long stuff before there was a road in America at all; and the passenger car out of which Mr. Huskisson descended to meet his death, on the memorable day that preceded the opening of the Liverpool and Manchester railway, was a double truck car much as we now see them, and what was more, it had seats with reversible backs, such as are now universal in America, though they were never commonly used in England. This identical car was

only used on the Liverpool and Manchester for a short time, and was subsequently sold to the Newcastle and North Shields, where numbers may still remember it as being occasionally used on the Sunday trains. The early history of railways begins altogether with the private unchartered roads of Great Britain, for although a railway company was chartered in the last century, and the first public railway that was actually constructed dates from the first year of the Nineteenth Century, all these early public roads were worked by horses, and contributed nothing of either scientific or mechanical interest until the Stockton and Darlington of 1825. During this quarter of a century, however, the private roads had solved most of the important mechanical questions upon which all the subsequent evolution of railways depends. Although the Mag. article speaks disparagingly of the results of all the experiments and investigations prior to the era of the Rocket, there were but few important points in railway practice unsolved at the date of the Rainhill experiments, either in the construction of the railway or of the locomotive. Since 1812 locomotives had been in constant daily use on a number of private railways, and these lines had been constructed and were being worked with just as rigid a regard to economy, and with as successful a record for economical work, as any of those subsequently laid down. The old Stockton and Darlington was laid out, not only with a strict regard to economy, but so as to make it the best and most perfect road that could be obtained between its termini, and it remains, to this day, as complete and finished a line as can be produced, nor is there in existence, as far as the author knows, anything very much superior to the old Quakers road, finished five years before there was a railway of any kind in America. Even the latest improvement introduced on the New York Central, for the advancement and recreation of their employees, might with advantage, take a leaf from the experience of the Stockton and Darlington 40 years since, on the management of the railway employees' reading, coffee and recreation rooms, which were the first to be introduced and are still perhaps the most successfully managed on this good old railway.

From Woods' "Treatise on Railways," the first edition of which was published in 1825, we learn that the date of the introduction of railways into the Newcastle district was between the years 1602 and 1649. These were entirely of timber. In 1738 cast iron rails were substituted for the upper stringer, which was made of hardwood and took the wear of the wheels. In 1747 the Colebrookdale Company replaced their wooden rails with cast-iron, and iron wheels were introduced in 1753. Tramplates of the section used by Outram had been

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