Canals and Railways on one level—Haulage on Railways—Railways in Scotland—Edinburgh and Midlothian, Stockton and Darlington, and Edinburgh and London Railways—Uniform gauge proposed—Notes on Railways for the Highland and Agricultural Society—Letter from George Stephenson.
Great powers of observation, combined with fertile and practical mechanical resources, enabled Mr. Stevenson in many cases to form engineering opinions which may truly be said to have been “before their time,” and in no subject, perhaps, was this more strikingly realised than in his views as to railways.
Impressed with the great inconvenience of change of level in canals, involving “lockage,” with all its expensive works and serious obstruction of traffic, he early formed a firm belief that wherever lockage could be avoided, by making even a considerable detour in the line of canal, it was sound engineering to adopt the level line, although it might be at the cost of additional length. Founding on this general opinion, so early as 1812, he traced out and proposed lines of canal to be carried upon one level, without lockage, through the valleys of Strathmore and Strathearn, connecting Perth, Forfar, Arbroath, and Montrose, and also by a line of canal, by Broxburn,112 Linlithgow, Polmont, Castlecary, Campsie, and Broomielaw, to unite Edinburgh and Glasgow.
His early researches on the subject of canals prepared him, about 1816, to extend the same reasoning to railways, which, with wonderful sagacity, he foresaw must become what he termed the “British highway” of the future. He found that his first idea of tracks of iron and stone to improve the draught on common roads was not destined to meet the requirements of the future; and when as yet nothing was known of railways beyond the tramways connected with coal-fields, and no proposal had been made to adapt them to passenger traffic, Mr. Stevenson was engaged tracing in all directions through Scotland lines of railway as a new mode of conveyance to supersede roads. Some of these early proposals, extending to about five hundred miles, are shown in hard lines on Fig. 15, and of all these railways he made surveys, estimates, and elaborate reports addressed to Committees of subscribers by whom the various schemes were supported.
It must be remembered that at that early period no other power than that of horses was contemplated for performing the haulage either on road, canal, or tramway, and Mr. Stevenson, true to his early views as to the disadvantage of lockage on canals, spent much time in experimenting on the prejudicial effect of steep inclines on horse railways, and in endeavouring, in his various surveys, to discover routes by which his lines of railway might be carried through, as much as possible, on one level, regarding a few miles additional length of line as quite unimportant compared to the disadvantage of a steep gradient,113—a view which was more appreciated before the locomotive engine had taken upon itself the labour of the horse.
Fig. 15.
To show the state of railway matters at the period to which I refer, I think it may not be uninteresting to give,114 even at some length, extracts from Mr. Stevenson’s report on what was called the Edinburgh Railway. The report, which is dated 1818, was addressed to “His Grace the Duke of Buccleuch and Queensberry, and the other noblemen and gentlemen, subscribers for a survey of a railway from the coal field of Midlothian to the city of Edinburgh and port of Leith.”
“In the course of a report relative to a line of canal upon one level, or without lockage, between the cities of Edinburgh and Glasgow, the reporter took occasion to state the practicability of a line of railway from the coal field of the vale of the Esk to the city of Edinburgh and the port of Leith, founded upon a communication which he had the honour to make to Sir William Rae, Baronet, and the Honourable Baron Clerk, so far back as the year 1812. This subject having since attracted the notice of Sir John Hope, Baronet, and several of the other landed proprietors of Midlothian, the reporter had consequently a correspondence with Messrs. Gibson and Oliphant, Writers to the Signet, on the part of the promoters of this measure.
“A public meeting was accordingly called by advertisement to be held in the Royal Exchange Coffee-house on the 3d day of September 1817, when John Clerk, Esq. of Eldin, having taken the chair, the reporter received instructions to survey a line or lines of railway from the Midlothian coal field to the city of Edinburgh and port of Leith; and he now submits the following as his report, with reference to the accompanying map or plan, and sections of the several lines of road surveyed.
“It is uncertain at what periods the inhabitants of Edinburgh were generally obliged to lay aside the use of timber, from the distance of carriage, as their chief building material, or of wood and turf as fuel; neither have we any certain information at what time pit coal was discovered, or the coal field of the Lothians first 115opened. But it is in the recollection of some persons still living, that, owing to the miserable and circumscribed state of the roads, or rather the want of formed roads altogether, pit coal continued to be conveyed in sacks and on horseback for supplying the city of Edinburgh. These horse tracks, originally taken up by accident, were persevered in by obstinate habit; and being afterwards followed as the lines of our future roads, have become the ultimate source of much of the difficulty attending their improvement, from the soft and miry track of the pack-horse and the sledge, to the broad and spacious stoned carriage-way, in combination with the trim footpath of the present day. But, even here, experience shows that it would be improper to rest satisfied, and cease from further exertion. The acclivities of the road may still be levelled, and its asperities smoothed, by the introduction of the more compact and durable materials of the British Roadway or Iron Bail. Such, however, has been the progressive nature of discovery in all ages, that we are only beginning to appreciate the immense advantages which would attend the introduction of a new system of roads or railways, laid upon a level or horizontal base, as admirably calculated to increase the power of the horse in a tenfold proportion by destroying friction—that bane to animal labour as now applied on the common road.
“Wagon-ways constructed entirely of square wooden frames or rails, laid in two right lines on wooden sleepers, appear to have been in use at Newcastle so far back as the year 1671. The plan of cast-iron railways seems to have been originally introduced by the great Iron Company of Colebroke Dale in Shropshire, only about the year 1786, as an improvement upon the tram or wooden railway; and such are likely to be the benefits resulting from this discovery, that we doubt not, as this system develops itself, the name of the person who first conceived the idea will eagerly be sought after, and honour done to him, as to one of the greatest benefactors of his country. We might mention the name of the116 late Mr. Jessop, as the first engineer of eminence who seems to have introduced railways in the south. He was also the engineer for the magnificent works of his Grace the Duke of Portland in Scotland, connected with which there is a double railway from Kilmarnock to Troon, which is ten miles in length. The other railways in Scotland of any extent are those at the works of the Carron Company, Lord Elgin’s, Mr. Erskine of Mar’s, Sir John Hope’s, and other coal works. A public railway has also been projected from Berwick-upon-Tweed to Glasgow, an extent of country of about 125 miles; and an Act of Parliament has already been obtained for completing part of this track, viz., from Berwick to Kelso.
“A railway has the advantage of being formed at an average of one third perhaps of the expense of a navigable canal; and in many situations its first cost may even be compared with the expense of making a common road. The result is also favourable if we inquire into the comparative quantities of work done upon a canal and a level railway. Upon the canals in England, a boat of thirty tons burden is generally tracked by one horse, and navigated by two men and a boy. On a level railway, it may be concluded that a good horse managed by a man or lad will work with eight tons. At this rate the work performed on the railway by one man and a horse is more than in the proportion of one third of the work done upon the canal by three persons and a horse, if we take into account the more speedy rate of travelling and the facilities to general trade in loading and discharging, together with the difference of the first cost of a railway, which altogether give it in some cases a decided advantage over the navigable canal. If we compare the railway with the common road, it may be fairly stated that, in the instance of a level railway, the work will be increased in an eight or ten fold proportion. The best horse, indeed, with difficulty, works with three fourths of a ton on the common road, from the undulating line of its draught, but on a level railway it117 is calculated that he will work even with ten tons. But to increase the economy of the railway system still further, we have only to employ one man to work two horses.
“Line of Draught.
“With regard to the line of draught, or longitudinal section of a railway, it may be stated as one of its great advantages that it is more easily accommodated to the irregularities of the ground through which it has to pass than a navigable canal; and even where the ground is so irregular as not to admit of a uniformly level track, or an inclined plane, there are several simple methods which may be resorted to for lifting the wagons from one level to another, so as to produce similar effects with lockage on a canal. In so far, however, as the present design of the Edinburgh Railway has been carried by actual survey, neither of these plans will be found necessary upon the main lines. Even on the descending line, the fall is so extremely gentle that the horses in returning may be loaded with four or five tons. But the proposed mode of lockage may with propriety be introduced on the several offset branches, such as those from Leith to the main line, and from Monkton Hall and the Cowpits to Dalkeith, and to the southern parts of the county, on which a trade may be expected to be carried both to and from the main line.
“Where the load or trade is all in one direction, it is a maxim in practice, that the fall should be so apportioned to the rise, that the work may be equal down with the load, and up with the empty wagons. But where there is to be a trade both ways, it is obviously much to be desired that a level in all such cases should be obtained. This, in the Edinburgh Railway, has been found from the declining aspect of the country towards the sea; but as there will be less return trade on this railway in merchandise and manure, etc., to the eastward, than the coal and building materials, etc., carried to the city, it becomes a question of policy how far it118 may be proper, in this instance, to adopt the level line at a great additional expense.
“By the level line to Edinburgh the branch to Leith becomes also somewhat more lengthened than by the descending line, which, instead of preserving the level, is always falling, or approaching towards Leith. The reporter, as before noticed, has various modes in view, by which the branch to Leith may be made of a very easy line of draught, or be thrown into a succession of levels, by a species of lockage or stepping. Where sudden acclivities occur on the line of a railway they are generally overcome by an inclined plane, of greater or less extent, according to the particular rise, and on this the loaded wagons are brought up by a steam-engine. But to render railways applicable to all situations, it seems to be necessary that the overcoming of such obstacles should be within the reach or power of the driver and his horse; by working a kind of gin connected with an inclined plane, or by lifting the loaded wagons perpendicularly, which may in various ways be accomplished by the aid of pulleys, by the common lever, or the revolution of a wheel.
“This subject has been justly considered to be a matter of so much public importance, that the Highland Society of Scotland has offered a premium for an Essay, with models, for lockage on railways; and the reporter has no doubt that by this means much additional light will be thrown on the subject.
“There are few subjects on which those conversant in the working of draught animals are more divided than about the proper line of draught. Some do not hesitate to affirm, that a level road is injurious to the horse, and that an undulating road is preferable to one by which the ascent is long, though gradual. Such are of opinion, that by throwing the road into successive eminences, or up and down hill, various muscles are brought into action, while others are left at rest, and this alternation they conceive to be the best condition of things for the animal.
119 “Being rather, however, at a loss in regard to that part of the subject which relates to the operation of the muscles, the reporter applied for a solution of the case to a distinguished medical friend in this city [Dr. John Barclay], eminent for his knowledge and for his great exertions in the science of Comparative Anatomy. His answer to the queries which he allowed the reporter to put contain the following comprehensive passages: ‘My acquaintance with the muscles by no means enables me to explain how a horse should be more fatigued by travelling on a road uniformly level than by travelling over a like space upon a road that crosses heights and hollows; and it is demonstrably a false idea that one set of muscles can alternately rest and come into action in cases of that kind. The daily practice of ascending heights, it has been said, gives an animal wind, and enlarges the chest; it may also with equal truth be affirmed that many horses lose their wind under this sort of training, and irrecoverably suffer from imprudent attempts to induce such a habit.’ In short, he ascribes much to prejudice, ‘originating with the man, who is continually in quest of variety, rather than the horse, who, consulting only his own ease, seems quite unconscious of Hogarth’s line of beauty.’
“In the course of investigating the subject of the draught of horses, the reporter has made several experiments with the dynamometer, both upon canals and railways, with a view to ascertain the power of horses and the best line of draught; and he has further the satisfaction to find, that the result of these trials agrees nearly with experiments made, and obligingly communicated to him, from various parts of the kingdom. The reporter therefore concludes that the force with which a horse will continue to work is about one-sixth or one-seventh of his absolute weight. Now, as he found the average weight of three ordinary cart horses to be about ten cwt. it may be assumed, generally, that a horse can continue to work with a force equal to 160 lb.; and allowing 40 lb., or one fourth, for friction, there remains 120 lb. to be applied to the120 load. In these trials, when the wagons were put in motion, it appeared, under favourable circumstances, that a force of about 12 lbs. only was necessary to move one ton upon a level edge railway, which by calculation would give about ten tons as the load of a good horse weighing ten cwt.; but, for practice, this will perhaps more properly be taken at about eight tons. With regard to inclined planes, it may be noticed, that for every one fourth of an inch of rise to the lineal yard of road, the force must be increased, or the load diminished, in a ratio or proportion varying at the rate of about one half, one third, one fourth, one eighth, and one ninth, etc.
“Such are the happy effects of a wise and extended policy, that, notwithstanding the expensive war in which this country has been engaged, more has actually been done in Great Britain, within the last twenty or thirty years, for the improvement of the highways, and in laying open the country by new and better lines of road, than was effected for centuries before that period. With such public improvements we presume to class the measure of the proposed railway from the city of Edinbu............