Autobiography of Sir John Rennie, F.R.S., Past President of the Institute of Civil Engineers / Comprising the history of his professional life, together with reminiscences dating from the commencement of the century to the present time.

by Sir John Rennie

The surveys for the line over Chatmoss were completed and deposited in due time, and the usual notices were given. The Bill was read a first time in the Commons, and after the second reading was referred to a committee. Certainly Bradshaw had not exaggerated the opposition, for the Bill was most energetically contested, the leading counsel against the Bill being the late able and amiable Baron Alderson. The Bill, however, passed the Commons, and ultimately the Lords, after an equally strong contest; but Lord Lowther and his friends were indefatigable, and to his lordship’s great exertions the success may be mainly attributed. At the time I was so completely prostrated by the effects of the fall which I had met with at London Bridge, as previously mentioned, that I was unable to take any very active part, which therefore chiefly devolved upon my brother and Mr. Vignolles. After the passing of the Bill, my brother and myself prepared working drawings and estimates for carrying the work into effect, and we naturally expected to be appointed the executive engineers, after having with so much labour and anxiety carried the Bill through Parliament. The Executive Committee of the Company behaved extremely ill to us. Stephenson, although he had failed in carrying the first Bill, still possessed considerable influence with the Executive Committee, who proposed that Mr. Stephenson should be united with us. We said that we had no objection to Mr. Stephenson taking the locomotive department, which should be distinct from the other works. This, however, the Committee declined, and at once appointed Mr. Stephenson the chief engineer, and Mr. Vignolles the resident.

My brother and myself designed that the width of gauge should be 5 feet 6 inches from centre to centre of the rail, and if this had been adopted we should never have heard of any other. This was the proper gauge for which an engine could have been made of the most powerful description, without being too long. Moreover, the centre of gravity being lower, it would have been more steady, being better adapted to going round sharp curves. The same advantages would have been gained by the passenger and goods carriages. Unfortunately, Mr. Stephenson was of a different opinion: he thought that the old colliery waggon gauge of 4 feet 8½ inches from centre to centre of the rail was ample, and it was adopted. Hence all the enormous litigation and expense which afterwards ensued. Brunel subsequently, on the Great Western Railway, feeling confident that Stephenson’s gauge was too narrow, proposed and ultimately adopted 7 feet as the proper gauge. Now this was as much too wide as Stephenson’s was too narrow. Stephenson’s party have ultimately prevailed, and the narrow gauge has been generally adopted, much to the efficiency and economy of railways.

Before leaving this part of the subject, it may be right to remark that the opposition endeavoured to make a strong case against our line crossing Chatmoss, which they said was utterly impracticable at any reasonable expense. This we knew from our own experience to be simply ridiculous, and so it was found to be during the execution; it has now proved to be the best part of the line, and the easiest to keep in repair. All that was required was to drain the surface by moderate-sized drains, so as to get rid of the superfluous water, then the foundation for the rails would be sufficiently solid to bear anything; moreover, it possesses a certain degree of elasticity which prevents the concussion or jolting that is usually found on a hard unyielding road. In 1828 the line was so far advanced that the Company determined to advertise for locomotives, and to give a premium of 1000l. for the best one that was produced. Amongst the competitors were Messrs. Stephenson and Lord, Messrs. Braithwaite and Ericsson, and Mr. T. Hackworth.

The competition took place at Rainhill. The Company restricted the weight of the engines to seven tons, which shows how little the subject was at that time understood, for the power of a locomotive engine is in proportion to its weight and the steam generated to work it; hence it was quite clear that in restricting the weight they restricted its power. Notwithstanding this, the engines performed wonders, and attained the speed of 28 to 29 miles an hour. This was so contrary to the general expectation, for even the makers did not expect above 8 or 10 miles an hour, that everybody was astonished, and from that time forward the glorious career of railways was established, and the old road system for goods and passengers was condemned as a thing of the past. The shares, which had been at a discount, now rose to a premium, and numerous new lines were in contemplation. Stephenson’s engine, the ‘Rocket,’ gained the premium, as it complied with all the required conditions, although that of Messrs. Braithwaite and Ericsson was in other respects considered the best.

The rails used upon this line were what is technically called the edge rail. These were of cast iron, weighing 30 lb. per yard, and they were cast on lengths 3 feet long, resting upon blocks of stone about 12 inches thick and 2 feet square, like the old tramways. Here is another example of the little that was known upon the subject; for it was forgotten that the old tramways were worked by horses, which seldom exceeded the speed of 2½ miles, and, consequently, the vibration upon a tolerably well made road was scarcely sensible, although it prevailed to a certain extent; but when the velocity was increased to above 20 miles an hour, the case was totally different, as should have been anticipated; yet the line was opened for traffic on the old principle, until it was found that the concussion and vibration produced by the rigidity of the road were so serious as to cause considerable trouble. On account of its elasticity, the Chatmoss section was found to be the easiest and best part of the road, yet it is singular that this did not occur to the Company. They continued to use stone blocks more or less up to the year 1837, when they discovered their error, and replaced the blocks with wooden sleepers, and large hillocks of these stone blocks may still be seen lying along the Manchester and Liverpool, and Birmingham lines.

But to return to the edge rail, which was certainly a great improvement upon the old flange rail. This edge rail was, I believe, first invented by William Jessop, a celebrated man of his time, and tried under Smeaton, who proposed it for the Leicester and Loughborough Tram Railway. The flange was transferred from the rail to the inner edge of the waggon wheel; and the edge rail having no flange occasioned less friction to the shaft. As the rails were manufactured of cast iron, they could not be made longer than 3 feet without materially increasing their liability to break; but there were so many joints that it was very difficult to make a smooth road and keep it in order, particularly when the speed of travelling increased. Hence the use of stone blocks had not been abandoned. This difficulty was at length overcome by the substitution of wrought-iron rails, which were first proposed by Buckenshaw. These were laid on wooden sleepers, and this was another great improvement; but the numerous joints were still a great difficulty in the way of making a smooth road and keeping it in order. This was at last overcome by making the rails in one single piece on rollers patented for the purpose.

Rails have now been increased from 30 to 80 lb. per foot, and have been fished at every joint; that is, a plate has been fixed on each side with sufficient room in the connecting bolt-holes to allow for expansion and contraction.

With regard to locomotives, numerous improvements have been made. We have first Watt’s idea of making a steam engine, with its boiler complete, upon an independent carriage, mounted upon wheels, so that it could move in any direction and propel itself; as well as a weight attached to it, mounted upon wheels also. As the tramways of cast iron were then established, this locomotive machine could have readily been applied to it, so that, in fact, to Watt may be attributed the first practical idea of the locomotive engine, although there are some doubts about this, for a M. Cugnot is said to have made a working model of a locomotive engine upon a considerable scale, at Paris, in the year 1783. Be this as it may, they were both made so nearly about the same time that it is difficult to decide which had the priority. At all events, Watt is justly entitled to the merit of having been the first to invent it in England.

Hackworth’s (of Darlington) engine was made about the same time, and was similar to Stephenson’s.

The next improvement consisted in placing the cylinders of the engine horizontally instead of vertically, so that the piston acted directly upon the axle upon which the driving wheels were placed, instead of by the intervention of a double crank; this made the engine more compact.