the accommodation can be increased, when necessary, by 50 per cent.
The modus operandi is as follows:—On the arrival of a set of waggons in the upper reception lines, the rear brakes are put on, the engine is detached, and then on each waggon is chalked the number of the sorting siding it has to enter. One man carefully inspects the brakes of each waggon, and calls out the chalked number to a second man standing below him, who has to regulate the speed of the descending waggons. This second man passes the number on by hand signal to the shunter lower down who has charge of the points, and who, by moving a lever, turns the waggon into its proper siding. The shunters are provided with brake sticks, which they insert between the wheel and the waggon-frame to steady the waggons in going down, and they also use these implements for letting down the brake levers when required. By the process thus described, each sorting siding now holds a separate train, although the waggons composing it are in indiscriminate order, but by a repetition of the operation, the waggons of each train are separated in the gridirons, and are lowered, one by one, into the departure lines, in the precise order in which they are required to be sent away.
Fig. 28 a also shows the apparatus known as the "chain drag," devised by Mr. Footner for arresting runaway waggons, which may occasionally get beyond the control of the shunters. This consists of a heavy iron chain cable, placed in a wrought iron tank between, and below, the level of the rails; a steel hook attached to the cable is fixed in a loose socket, at the height of a waggon axle, and is worked by a lever which also works a signal.
