THE USE OF PIPES. 



53 



duly interrupted by friction, upright pipes or hydrants 

 are attached which project at least three inches above the 

 surface of the soil. These are about 200 feet apart. They 

 are furnished with valves which operate by means of a 

 square head and a key. Each one is fitted with a cap 



Fig. 21. IRRIGATING BY PIPES AND HOSE. 



which screws on or off, and which is attached to the hy- 

 drant by a short chain for its preservation. When this 

 cap is unscrewed a section joint affixed to the end of the 

 hose may be screwed in its place. 



When this apparatus is in operation, the water descend- 

 ing from the elevated tank or reservoir passes through the 

 pipes and the hose, and escapes with some degree of force, 

 depending upon the hight of the head, through a flatten- 

 ed nozzle, which scatters it in a thin sheet or broken 

 shower. With this apparatus one man may water copi- 

 ously five acres of ground in a day or night. Each hy- 

 drant being the center of a plot 200 feet square, serves 

 to irrigate, with 100 feet of hose, very nearly or per- 

 haps one acre of ground. To irrigate five acres in 10 

 hours would give an hour and a half to each plot, an 



