IRRIGATION AND DRY-FARMING 697 



Fig. 76. — 'Essential features of construction in one method of overhead 

 spray irrigation. Water is supplied under pressure from under- 

 ground pipes and is distributed from small nozzles (N) along the 

 axis of the pipe. Different forms of nozzles are used for different 

 purposes (see detail). Gauge (G) shows pressure, (S) is pipe sup- 

 port, and (L) is lever for turning the discharge pipe, which is fitted 

 with a freely moving sleeve joint. 



