in presence of this state of things—that, while the outwards traffic at Edge Hill had grown from 257,025 tons in 1850 to 1,032,853 tons in 1873, the siding accommodation had only been increased from 1,782 waggons to 3,215 waggons; in other words, the business had quadrupled, while the facilities for dealing with it had only been doubled. It may here be said, that, at the present time, the area occupied by shunting lines and sidings at Edge Hill is 200 acres, and that there are 57 miles of running lines, and siding room for nearly 6,500 waggons.
At the period mentioned it became necessary to consider seriously how the difficulties were to be met, for, in addition to the want of room, the main passenger lines had to be crossed every time waggons were moved from one group of sidings to another (and there were a great many groups), so that there were serious obstacles to be encountered in carrying on the working, and as the safety of the passenger trains always had to be the first consideration, the goods traffic had often to suffer delay.
The Company had, at that time, about 70 acres of spare land on the north side of the railway, and available for extension, but to reduce this to the level of the main lines would have involved a stupendous amount of excavation, and the fact that the surface of the land rose from west to east, and that, for a comparatively reasonable outlay, sidings could be laid upon it on a uniform gradient which would enable them to pass over the branch line running round to the docks, which branch line intersected the land, suggested to Mr. Footner a scheme for marshalling by gravitation. In considering a scheme of this kind two things appeared to be essential—first, that in the passage of the trucks
