ENGINES, MOTORS AND TRACTORS 



753 



in construction and 

 often may utilize 

 water where other 

 types of more efficient 

 wheels cannot be 

 employed. 



Impulse Water 

 Motors. — I m p ul s e 

 water motors are 

 provided with buckets 

 around the circumfer- 

 ence of the wheel 

 against which a small 

 stream of water under 

 high pressure oper- 

 ates. The Pelton 

 wheel is one of the 

 most efficient of the 

 water motors, but re- 

 quires for successful 

 operation a head of 

 water considerably 

 higher than is required 

 by most of the other 

 water wheels. This 

 type of wheel may be 

 secured in sizes under 

 one horse power and 

 up to several hundred 

 horse power. 



Turbine Wheels. 

 — The turbine is a 

 water motor which is 

 built up of a number of 

 stationary and move- 

 able curved pipes. It 

 consists of the follow- 

 ing parts: 



A guiding ele- 

 ment which consists 

 of stationary blades 

 the function of which 

 is to deliver the 



Pelton Watek Wheel. 1 



Turbine Water Wheel. 2 



1 Courtesy of Pelton Water Wheel Company, New York. 



2 Courtesy of J. and W. Jolly Company, Holyoke, Mass. 



48 



