In the first plan which we shall notice, waggons or carriages of any kind, as also boats on carriages, having wheels to correspond with the breadth of the railways, will continue as horizontal in passing up and down inclined lanes, even of 450 of elevation, as if travelling upon a level railway. The first idea of this, was to construct waggons on purpose for ascending and descending 'moil these steep inclined planes ; but an improvement was afterwards thought of, by which carriages of almost every description may pass up and down these inclined planes, provided that their wheels be fitted to the railways.
All public lines of railway will require two distinct sets of railway tracks, and, consequently, the inclined planes upon it must be fitted up with machinery that will tale up carriages upon the ascending plane, either empty or loaded, at the same time that empty or loaded carriages are passing down the descend ing plane ; and. in like manner, let down on the descending plane either empty or loaded carriages, when there are neither empty nor loaded carriages to pass up the ascending plane: all such properties are requisite for general service on a public line of railway. Inclined planes that have upon them ascending and descending tracks, are called double inclined planes ; but those about to be described may be called double-railed inclined planes, as both the ascending and descending planes have two sets of rails.
The first step to be taken towards the formation of these inclined planes, is to commence at the foot of the acclivities that are proposed to be ascended and descended, and to cut forward a level roadway of a necessary breadth for a double railway, not having less than four feet in breadth between the two rail ways, until a perpendicular height is gained of from eight to ten feet. This face is not to be left perpendicular, as in the last proposed method, but is to be sloped away towards the rise of the acclivity with an uniform regular shape, until it forms an angle of 450 with the horizon, or an outward angle of 1350 with the level line of the railway. At the top of this inclined plane we again commence and cut forward a similar roadway, until the face of the cut be such as will admit being formed into another inclined plane, like to the fiat ; and, in like manner, continue to cut forward roadways and form inclined planes, all the way to the top of the acclivity, or else to a height where it may be judged proper to strike off with a level railway. All these steep slopes are to be care fully flagged with well-dressed durable atonee, laid in lime ; and the sides of the roadways are to be properly built with a face-building, until it reach near to the foot of the paved slopes. Strong walls are also to be built on each side of the slopes with large hewn stones: the tops of these walls are to be carried up parallel with the slope of the pavement ; and the height of each of these walls, measuring at right angles with the pavement, may be three feet; and they are to be carried up to a level with the upper roadway. A middle wall of strong mason-work, of four feet in thickness, is to be built exactly up the middle of the paved elopes, corresponding precisely as to height and slope with the side walls, and which are also to be carried to a level with the upper roadway.
Matters being thus far arranged, the next step is to lay all the level roadways with rails, so as to form railways of about four feet three inches between the tracks. Rails are not only to be laid along level roadways, but they are also to be laid up along the inclined paved planes, in a secure and substantial manner. There is, likewise, a rail to be laid upon the top of each of the side walls of the inclined planes, in a parallel manner to those upon the pavement, and which are to be securely fixed within three inches of the face of the walls. The length of a horizontal line between the rails that are upon the pavement, and those that are upon the top of the side walls, will be found to be (at the height that these walls are proposed to be built) four feet three inches, nearly. Now, "if a carriage be made with two pair of wheels, all of the same diameter, having its fore-wheels to correspond with the railway-tracks that are upon the pave ment, and its hind-wheels with a longer axis, to correspond with the distance between the rail-tracks that are fixed upon the top of the side walls, and the axles of the two pair of wheels placed at the calculated distance of four feet three inches from each other,—then will the;body of such a carriage, when pass ing up and down these inclined planes, remain equally level as if travelling along level railways. A carriage, such as we have described, could not travel along
a railway with single rail-tracks, owing to the axles not being both of one length ; and to have a railway on each side, would be attended with much additional expense ; or to have small rollers on projecting ends of the hind axles, would give the carriage an awkward appearance; therefore, the following method is proposed • which is, to sink a place at the foot of the inclined planes, of a length, breadth, and depth it to receive a platform carriage with four wheels, its fore ones to fit the rail-tracks on the pavement, and its 'hind wheels to fit the tracks that are on the top of the side walls. Upon this carriage two rails are to be fixed, to correspond exactly upon the level railways, and to butt against them. A stayed iron draught-bar is to be strongly fixed to each side of this carriage, to fasten the ropes to, by which the machinery is employed to raise up or let down the carriages. The position of the draught-bars will be regulated by the centre of gravity of the weight that is to be brought up. From this arrangement it will appear, that a waggon, such as we have placed upon it, or any cart or carriage whatever, that has wheels corresponding with the rail way, will readily enter upon these platform carriages, which may easily be pre vented from running off, while ascending or descending upon the platform, by means of a piece of chain fixed near to its fore end. As these platform car riages are only intended to pass alternately up and down the inclined planes for carrying the railway carriages, it is requisite that, on reaching the top or bottom, the rails shall also correspond, that the waggons may leave the platform on the chain being unhooked that is to prevent them from running prematurely off: An experiment was made upon a railway having a declivity of twelve and a half inches in 100 feet of length, with a loaded coal-waggon, whose weight, including the carriage, was two tons. A middle-sized old man pushed this waggon down the declivity, and gave it a considerable motion ; the waggon was stopped when the same old man set his back against it, and brought it up to the above-mentioned acclivity, without much apparent difficulty. This is stated to show, that where the distance between the inclined planes is short, the carriages may be pushed along by one man upon a level railway ; or he might be put in possession of a kind of acceleration to be wrought by treadles, by which be cold employ both his weight and his strength by laying hold of two handles to give greater power to bis feet. Or, in place of cutting forward a level roadway to the ascending plane, it may be cut with an easy declivity, and the railway to the descending plane with a gentle acclivity, by which the carriages, on being put in motion by hand, would run of themselves to the, inclined planes. By forming the roadways in this manner, the ascending plane would become some what more, and the descending plane somewhat leas, in height, than they would have been had the roadways been level; but as it may be best to have both inclined planes of the same length, it will only be necessary to make the descending plane with a longer slope ; for although 450 is here mentioned, there is no necessity for adhering to that angle. Where the distance between them is great, the level railway, and a horse to be employed to pull the carriages between them, is to be preferred. Although it is practicable to make inclined planes, upon the same principle as those described, to take up more than one waggon at a time, yet the power that would be required, and the several disad vantages that would attend it, are such as will much more than counterbalance any advantage or gain to be made ; for which reason there need be no hesita tion in recommending the taking up or letting down only single waggons at a time ; and possibly it may be found that the most beneficial and eligible weight to be carried will not exceed two tons, including the weight of the carriage.