20 



BULLETIN 495, l'.. s. DEPARTMENT OF AGRICULTURE. 



carry the full bead of water. As the water is diminished by each 

 nozzle the pipe can be reduced in size, finishing with a f-inch pipe 

 at the extreme end. The customary sizes of pipe used for the nozzles 

 now on the market are set forth in Table 1. 



.Table l. — si~i :s of i>ii>c used for nozzles now on the market. 





Total 



length 



of line. 



I-incli 

 pipe. 



1-ilirh 



pipe. 



1',-inch 



pipe. 



r.-iiuh 

 pipe. 



2-inch 



pipe. 







Feet. 



150 

 200 

 2E0 



300 



400 

 500 

 600 

 700 

 150 

 200 

 250 

 300 

 400 

 500 

 I 600 



Feet. 

 150 

 130 

 100 

 100 

 90 

 90 

 90 

 90 

 115 

 100 

 90 

 90 

 SO 

 75 

 75 



Feet. 



Feet. 



Feet. 



Feet. 





70 

 150 

 150 



ICO 

 160 

 160 

 160 

 35 

 100 

 100 

 100 

 100 

 100 

 100 











... 



. .. 





50 

 150 

 150 

 175 

 175 













2, outdoor, 4 feet apart, or No. 1, 3 feet 







100 



175 

 175 



100 











60 

 110 

 120 

 120 

 120 



1 







apart. 



100 

 120 

 120 



85 

 185 



Nozzle lines are spaced such distances apart as will best fit the 

 field within a range of 50 to 56 feet. The type of nozzle line de- 

 pends principally upon the method used for supporting the pipe. 

 The three popular methods are: On tall posts, on short posts, or on 

 cables suspended from high posts. 



Tall-Post Type. 



When tall posts are used they are set in the ground 2} to 3 feet 

 and cut off about 61 feet above the ground (fig. 13). These posts 

 are spaced 15 to 20 feet apart and the nozzle line placed on the tops 

 in roller bearings in the case of long lines and between nails in short 

 lines. If the post is of wood it should be not lighter than 4 by 5 

 inches, but a round post 5 to 6 inches in diameter will serve as well. 

 A more durable but expensive post can be made from a 1 or l{-inch 

 steel pipe set in a base of concrete 6 inches in diameter and 2 feet 

 dec]) (fig. 12). Special concrete posts also make excellent supports. 



Where wooden posts are used it is advisable to treat the part going 

 into the ground with a good grade of paint, tar, or creosote, to help 

 preserve the wood. The treatment should extend (> inches above the 

 ground surface. 



The tall posts permit the passing of horses or men under the pipe 

 and obviate obstruction to cultivation. This is the most popular 

 method and makes a good appearance when the posts are carefully 

 lined and cut off at the tops so that the pipe will lie straight, or uni- 

 formly curved with the surface of the ground. 



