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In the twentieth number of the Foreign Quarterly Review there is an article on locomotive engines and railroads, in which it is asserted, that “ every attempt yet made to render steam carriages on railroads the means of economical and regular inland communication has totally and absolutely failed.”
The following is an epitome of the argument by which this proposition is supported. It is laid down as a principle that steam will be superior to water, or wind, or horse-power only when it can be more easily, uniformly, and economically applied ; and then it is maintained, that as yet it has not been more economically applied than horse-power, in consequence of the immense expense which has attended every plan which has been tried. For it appears, on examining the half year's account to July, 1832, of the Liverpool and Manchester railway company, printed for the use of the subscribers, that the repairs of the railway cost 73311. in the preceding six months, and that the repairs of the engines in the same period cost 10,582., making the amount of expense for repairs in a year 35,826l., on a line of railway of thirty miles, being at the rate of 11941. a mile.
The article proceeds to state, that the cause of this vast expense is the huge, disproportioned,
and clumsy masses of mechanism of which the steam engines consist : these would produce, by their weight and jolts, their own rapid destruction, as well as that of the railway, if it were not for the repairs which are constantly going on. This injury to the engines is occasioned in consequence of having no contrivance to prevent the jolts from being communicated to them which the wheels are exposed to in passing over the railway; and these jolts are occasioned by the unavoidable defects common to all railroads ; for a railroad is not, by any means, what many suppose it to be, a perfectly smooth and even road of metal; but being composed of separate rails of iron, laid one following another, in lengths of not more than six yards, there are frequent breaks in the line, although almost imperceptible, in consequence of its being impossible to make perfect joinings of the rails, owing to the necessity of openings being kept between them to admit of their expansion and contraction with the variation of the temperature. In addition to this, the rails are not supported uniformly, by lying on the surface of the road, but rest on stones or sleepers, placed at the distance of a yard from each other. According, therefore, as heavy weights pass over the rails with great velocity, these sleepers are driven deeper into the ground, some more deeply than others, so that the surface of the line of rails becomes uneven.
Though this defect is not easily detected by the eye,
it appears on close examination with instruments, and on watching the motion of a carriage ; for the wheels, on passing every joining of the rails, receive a jolt which causes a change of direction, first towards one side and then towards the other: hence the carriage rolls very much, whilst at every swing one wheel or the other strikes a rail with considerable violence.
In order to remedy the great defect of having no contrivance to prevent the jolts from being communicated to the engines which the wheels are exposed to, an arrangement is indispensably necessary for supporting the carriage body and the whole moving machinery upon flexible springs, so that the whole may vibrate freely in every direction, and yet admit of its being impelled forwards with uniform power and velocity. But to apply a continuous force to wheels through a set of springs from a machine that is permitted to swing backwards and forwards, so as to be now nearer to them and then further off, implies a combination of stiffness and flexibility which seems an absolute contradiction. Such an arrangement requires that those parts should
be rendered movable, which it is of the greatest importance to preserve immovable.
The article here quoted concludes by observing, -“But the failure which has hitherto attended all attempts at the steam carriage, it is right to say, has arisen, not from any necessary incompati
, bility between the nature of steam, and the particular application of its power to railroads, but from the deficiency of the inventions, in some of the great elements of structure that are essential to its success.
“We may, therefore, still look forward to the substitution of its use for horse-power in bringing about a great and beneficial change in the moral, political, and commercial state of the empire.” *
In situations where canals cannot be constructed, either from want of water, or other circumstances, and where the description and quantity of traffic, or local obstructions, do not justify the expense of forming a railroad, paved roads made on proper principles would be found much better for conveying goods than turnpike roads, constructed as they usually are.
See No. 20. of the Foreign Quarterly Review, Article VII.
The advantages which may be derived from paved roads, as means of transport, have been too much over-looked; and therefore it is very important to show how much superior a well made paved road is to a common road in enabling horses to draw very large burdens.
On a smooth, well made pavement, quite horizontal, it appears, from the experiments made with Mr. Macneill's machine, that the resistance to draught is not more than the 100th part of the weight of the carriage and its load, when the carriage is properly constructed, and mounted on straight and cylindrical axles. * According to this a horse of great power would be able to draw on such a road, if horizontal, six tons and three quarters; and if with no greater inclination than 1 in 50, two tons and a quarter.
The following statement on pavements is taken from the evidence of Mr. Walker, given before a select committee of the House of Commons, upon the Commercial Road from London to the West India Docks:
“ It is not, I am sure, overstating the advantages of paving, but rather otherwise, to say,
See Seventh Report on the Holyhead Road.