302 RAILWAY CONSTRUCTION. 



have been a serious item, and where suitable timber was fortu- 

 nately close at hand. 



In cases where engines are watered direct from a water-tank, 

 a simple delivery-valve, as shown in the sketch (Fig. 458), will 

 answer the purpose. This valve has to be pulled open by the 

 chain and lever, D, and when released falls with its own weight, 

 and is kept close by the pressure of the water above. The 

 delivery-pipe should not be less than 7 or 8 inches in diameter, to 

 accelerate the filling of the tenders. Where water has to be 

 delivered to engines at two or more places in a station-yard, and 

 the supply derived from the same principal tank, the result may 

 be obtained either by laying down 7 or 8-inch main pipes from the 

 principal tank to separate water-columns, or by erecting two or 

 more pedestal water-tanks, similar to Figs. 459 to 462, each of 

 which holds a little more than the average quantity for one tender, 

 and can be fed from the principal tank by a comparatively small 

 pipe of 3 or 4 inches in diameter. It is simply a question of 

 expense whether it is cheaper to lay down a long length of 7 or 

 8-inch main pipe and ordinary water-columns, or to adopt the 

 small pipes and pedestal tanks. 



Figs. 459 to 462 are sketches of a medium-sized pedestal 

 water-tank to hold 1200 gallons. The supporting column must 

 have a very wide base, bolted down to a solid foundation. The 

 tank itself, made circular in plan, is generally constructed of 

 light plates of wrought-iron or steel, the lower portion or floor 

 of tank being very securely attached to the vertical column. 

 Notwithstanding their top-heavy appearance, these pedestal 

 tanks can be made very firm and steady if enough width be 

 given to the base-plate, and the tank properly fixed to the 

 column. Water is led into these pedestal tanks by a small pipe 

 passing up inside the supporting column, and the delivery may 

 be effected by a simple valve, as explained for Fig. 458. 



Fig 463 shows one type of water column for watering engines. 

 The wide base-plate is bolted down on to a foundation of stone- 

 work, brickwork, or concrete, and the main supply pipe (not less 

 than 7 or 8 inches in diameter) is carried up inside the column, 

 and connected with the screw valve, A, which regulates the 

 delivery to the tenders. The curved top, which forms the outlet, 

 and carries a leather hose, works on a swivel joint, and can be 

 swung round, either to the right or left, for convenience of 

 supplying engines on one or two standing-lines. The delivery 



