The Mechanical Handling and Storing of Material

COAL TIPS OR HOISTS 565 the stage moves upwards, as all four chains are tightened equally through pulleys h and I. When the stage has reached the level of the discharge shoot, the water is shut off at x and turned on at x', which has the effect of lifting the stage from point c by the chains passing over pulley g, and so tilting it to a slanting position, which discharges the truck. The stage is then levelled again, by allowing the water to escape out of x and then out Fig. 790. Second Hydraulic Tip at Rotterdam. of x, so that it drops by its own gravity; it is operated from point H, but there is an automatic stopping gear at the highest and lowest position actuated by the lod S. The weight of the stage itself is balanced by the weight Q, which hangs on a chain, the two ends of which are attached to a and B, and pass over the sheaves a, b, c, d. T T are two points from which the discharge of the trucks can be observed, and helped by hand if necessary. A small crane with skip K is also provided for lowering coal in smaller quantities