44 



BULLETIN 906, U. S. DEPARTMENT OF AGRICULTURE. 



Fig. 23. — Overflow stands. 



diversion. The valve 

 is controlled by a float 

 in an auxiliary stand. 

 Such an arrangement 

 would have v a hi e 

 where high pressure 

 pipe is laid down a 

 steep g r a d e , and 

 where relief stands 

 would have to be ex- 

 cessively high to back 

 water up to all points 

 of diversion. In the 

 above case, water was 

 intended to be used 

 for domestic use and 

 some provision was 

 necessary to keep con- 

 siderable pressure at 

 each diversion point. 

 It was not practicable to allow the entire head of water on the pipe 

 on account of the steep grades and long length of the main, and relief 

 stands at frequent intervals, high enough to deliver water to the 

 second story of a house were too expensive, and at the same time 

 unsightly. 



DISTRIBUTING HYDRANTS. 



After water has been conveyed to the field or orchard, the type 

 of distributing hy- 

 drant or valve should 

 be selected to suit 

 the soil, grades, and 

 crops to be watered. 

 The most common 

 type of valve con- 

 sists of a stand of 

 one length of con- 

 crete pipe that is 

 fitted with a number 

 of small gates (figs. 

 25 and 26), the size 

 of the stand and 

 number of gates de- 

 pending on the num- 

 ber of furrows to be 



Supplied from one jo IG . 24. — A diversion stand with covered top and valves 



