1850 - Railway Gradients

The Sydney Morning Herald Wednesday 27 November 1850

To the Editors of the Sydney Morning Herald.

GENTLEMEN, — Although public excitement has considerably worn away with respect to the conflicting statements which have been publicly expressed with regard to the engineering difficulties in the proposed Sydney rail- road, in circles competent to discuss the question it has been by no means dropped, and at present a great diversity of opinion, and it seems to me a considerable misapprehension of existing facts pervade the minds, both of individuals and the community, on this important subject. Having been connected with railways in England for some years, I have been appealed to to decide some differences, and the responses I have made, have induced some of my friends to request me to state my opinions publicly ; and I now do so, the less reluctantly because all personal controversy is over, and the whole of my remarks will be confined within the limit of a few statements of facts.

It appears to me that the controversy which has been maintained between Mr. Sheilds and Mr. Holland, and the supporters of each of these gentlemen, has assumed a false ground. The question between them has been argued—not from facts as they now are, but as they once were — the impediments to difficult railway transit which once existed have since been overcome, a fact which seems to have been overlooked by both parties, and though under the circumstances which each of the disputants relies upon, I presume to give no opinion on the theories of either, yet it seems that in the pro- gression which railway science has of late years made, the discussion of either of these theories is absolutely useless for all practical purposes.

Mr. Holland argues correctly in stating that steep gradients are scarce on the English lines, and that they are avoided by eminent engineers ; but he is wrong in stating that there are no such gradients in England as 1 in 70 worked without assistant power. Mr. Shields may be injudicious in his apparent advocacy of steep gradients, but certainly his information as to the capability of locomotive power in England at the present time is more correct than that of his opponent. Mr. Shields says, that on the Manchester and Leeds railway, a gradient of 1 in 59 has been surmounted by locomotive power, and that for a shorter distance 1 in 49 has been accomplished ; and on other lines 1 in 50 to 1 in 100.

Now it must be remembered that in the last few years many difficulties which were formerly thought insurmountable hove been overcome ; that engines have been enlarged and improved; and locomotive power now performs tasks which once were thought impracticable by the most sanguine and enterprising engineers. In 1834—as may be found from books of authority—there were five engines on the Liverpool and Manchester line, the weight of each being from eight to eleven tons, and one of these engines, weighing only eight tons, ascended the Sutton plone incline—1 in 89—with a tolerably heavy train, and without assistant power. The same engine accomplished the same day the Whishton incline—1 in 96.

I will now speak to facts within my own knowledge—having been employed both in the construction of engines and on various lines of railway in England since 1812. During that period, with I hope some prac- tical knowledge of engineering, I have acted in the capacity of engine driver, and therefore may safely speak as to the capabilities of the engines with which I have been acquainted.

On the Manchester and Birmingham line for some months I drove the Company's engine, No. 32, weight about 34 tons ; an engine frequently conveying a train of 700 or 800 tons, and guaranteed to carry 1000 tons. An engine constructed precisely on the same principle, and of the same size, used constantly to carry heavy trains up the Lickey incline on the Birmingham and Gloucester line (1 in 37½) without any additional power.

With regard to the Manchester and Leeds line, which Mr. Holland particularly refers to, I beg to state that I have frequently gone over the incline of 1 in 59 for 1000 yards, and 1 in 47 for 610 yards, alluded to by Mr. Shields, with a good strain, and without any assistant power. In fact the stationary engine has been removed.

In addition to the above facts I beg to quote the following passage from the third volume of the Practical Mechanics' and Engineers' Magazine, It occurs in a passage of a letter from Mr. Edward Portwine, on the merits of a new locomotive engine employed on the Edinburgh and Glasgow railway. The engine was a new one, 22 tons weight. "The incline I find is fully a mile and a quarter in length, and a full mile of it passes through a tunnel. The gradient I observe you have stated to be 1 in 44, but I was informed that a considerable part of it was not less than 1 in 40. Till now, as known to all your readers, the trains were drawn up by a pair of stationary engines, by means of an endless rope. By the employment of stationary power, in this way, considerable loss of time occurred, at least relatively, and which in the opinion of Mr. Paton, might be saved by the application of locomotive power. This opinion has been carried into effect most successfully. A friend and myself were invited to take our places on the driver's platform, Mr. Paton noting as driver on the experimental trial, and away started the puffing monster like a thing of life up the incline, at a rate full twenty miles an hour, with a heavy train of 17 carriages. Although the engine was 22 tons in weight, it was perfectly under control of the breaks in descending."

It therefore appears to me, that though discussion may arise as to the performances of small engines some 10 or 15 years ago, that all the difficulties which have been enumerated are easily surmountable by the large engines at present in use, on all the great English lines. These engines are sometimes four-wheeled, sometimes six, and are coupled by connecting rods. The four-wheeled engines are used for quick passenger trains, the six-wheeled for goods' trains, and they carry these trains, of ordinary size, up all the inclines on the Leeds line, without assistant power. On the Sheffield line—one of the heaviest in England for curves, before the six-wheeled engines came out, two or three engines used to be applied for bringing in the trains if the load was heavy ; now the large improved engines easily accomplish the journey.

I have no doubt that engines such as I have described would accomplish safely all the gradients on the line proposed by Mr. Shields, and I am happy to be informed that the company propose to import four-wheeled coupled engines such as I have described. These engines are to be fifteen inch cylinder, and from my own practical experience I can state such engines to be good and durable, and the best fitted of any within my knowledge for performing their work on a properly constructed line.

I am, gentlemen, yours,
Sydney, November 23.

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