USE OF CONCRETE PIPE IN IRRIGATION. 53 



supplies. They may be connected to concrete stands fitted with small 

 gates or flumes and galvanized pots fitted with spouts may be used 

 to feed the furrows. Some orchardists have utilized short lengths 

 of standard three-quarter-inch steel pipe to distribute water to the 

 furrows. Water is distributed through small holes bored, in the 

 pipe, each hole feeding one furrow. In the latter case a connection 

 is made to the iron pressure pipe at every tree row. The distribut- 

 ing pipes are about 8 feet long, and are fitted to the riser by pipe fit- 

 tings so that the pipe may be let down on the ground when irrigat- 

 ing, or set up vertically out of the way of cultivation. 



As regards irrigation gates and valves, it is a safe plan to install 

 makes that have all threaded or sliding parts either of brass, bronze, 

 or other composition metal that will resist rust. Gates whose wear- 

 ing parts are cast iron throughout are liable to corrode and stick. 

 Cast iron, however, is satisfactory for parts that do not wear, or 

 for seats to make a water-tight connection. Most gates are con- 

 structed to work with the water pressure, the pressure tending to 

 make them more water-tight. There are a number of pressure gates 

 manufactured that are held against the pressure by being clamped 

 tightly against the frame. Most gates are not built for heads over 

 15 to 25 feet. Special gates can be ordered for higher pressures. 

 It is better, however, to construct boxes so that pressures will tend 

 to hold gates in place whenever possible. 



An average price for pressure gates including frames was about as 

 follows July, 1919 : 



6-inch $5. 75 



8-inch 8. 00 



10-inch '___ 10. 00 



12-inch 16. 00 



16-inch 28. 00 



18-inch 36. 00 



These gates are fitted with a locking device that will hold the gate 

 in any position, and are used both against and with pressure. Plain 

 gates without the locking device sell for one-half to one-third of the 

 above price. 



Orchard valves for controlling water from pipe line to hydrant 

 stand sell for about as follows : 



6-inch $1. 25 



8-inch 1 1. 50 



12-inch 4. 00 



Alfalfa valves without hoods cost about $4.50 for 6-inch size ; $6.75 

 for 10-inch, and $9 for 12-inch. Portable hoods or hydrants for 

 flooding or for use with light-weight portable galvanizecl-iron pipe 

 cost about $12.50 for 6-inch hydrant and $18 for 12-inch size. 



