PUMPING WATERS. 93 



For driving ordinary three-throw pumps a belt may 

 be employed driving on to the counter shaft of the 

 pump as shown in the illustrations. The engine 

 must be started with the belt on the loose pulley, 

 and when it speeds up and is firing every fourth 

 stroke, the belt is shifted to the fast pulley, from 

 which it should always be removed before closing 

 down. A much better arrangement is, however, 

 where the engine drives the pump by gearing. In 

 this case the pinion on the engine shaft should be of 

 raw hide to reduce noise and wear. A friction-clutch 

 connects up the engine and pump when the latter is 

 running normally. Such an arrangement, together 

 with other details of a typical plant, is shown in fig. 

 78. Gas or oil engines may be vertical or horizontal ; 

 the writer is inclined to favour the vertical pattern 

 when all other points are in its favour. 



Oil engines are now made of the high-speed type, 

 very similar to the motor-car engine, and appear to 

 give satisfactory results. 



The remarks on gearing, etc., only apply to those 

 pumps which must run at a speed below that at 

 which the engine can economically run. Daniells' 

 pumps, the Hatfield pump, and centrifugal pumps 

 do not want gearing, but the latter may have to run 

 by belt at a much higher speed than the engine. 



On estates the steam engine does not now usually 

 exist, but, where a supply of steam is handy, the best 

 type of small pumping engine is the direct acting 

 type, either duplex, with positively-moved valves, or 

 the simple, with steam-moved valves. Pumps of the 

 " weir " type are very simple and economical. Where 

 electric light exists on an estate, the power may be 



