The Mechanical Handling and Storing of Material

6io THE MECHANICAL HANDLING OF MATERIAL brought to rest and their positions reversed. They then take the points leading to the hoppers where they discharge their loads and run back on the ‘ empties road. 1 he ease and rapidity of the process, the small number of men employed, and the absence of costly machinery are features which stamp this plant with the character of an ■engineering feat of the highest order. If such staiths were introduced into districts where the end discharging wagons are in vogue, the erection of a simple gantry over each hopper would enable these vehicles to tip their loads, so that they could be continued in service until gradually replaced by high capacity hopper wagons. Bogie wagons of any length could easily be accommodated, and owing to the diminished friction of large wagons fitted with axle boxes for oil lubrication, the gradient of the roads might be reduced.”1 The gravity system of loading is almost universally used in the United States and also in Spain where existing conditions permit of its use. It might be mentioned that an installation in the South of Spain can load as much as 8,000 tons in twenty-four hours from one double-sided installation, entirely by gravity, without the expenditure of any power, and with the assistance of only twelve men. 1 See “Capacity of Railway Wagons as affecting Cost of Transport,” by J. D. Twinberrow {Proc. Inst. Meeh. Engineers, 1900, page 573).