USE OF CONCRETE PIPE IN IRRIGATION. 7 
is rectangular in cross section, 36 inches by 36 inches inside dimen- 
sions. Collapsible wooden forms were used, 12 feet in length, with 
triangular reinforcing wire mesh placed in two sections. One section 
of wire mesh is laid on top of the forms, with the edges turned down 
into the side walls, and the other section covers the bottom and ex- 
tends up the sides. The sides of the earthen excavation were cut so 
as to leave a thickness of concrete of 6 inches. This conduit is made 
to stand 50 feet head. The total cost was about $2.40 per foot. 
If continuous pipe is laid in cool weather and is not allowed to dry 
before being filled with water, there may be no trouble with contrac- 
tion cracks, but this class of pipe would probably give considerable 
Fig. 2. — Showing one method of building continuous reinforced-concrete pipe. 
trouble if laid in the summer, especially if allowed to dry out dur- 
ing the winter. If possible, the pipe should be covered with at least 
2 feet of earth, and if the soil is kept moist curing should take place 
without the concrete cracking. 
One firm in Los Angeles has given the following prices at the 
yard, Los Angeles, under date of May, 1919, for reinforced concrete 
pipe : 
Diameter. 
Price per 
foot. 
Diameter. 
Price per 
foot. 
12 inches 
80.86 
1.13 
1.24 
1.37 
1.70 
33.30 
16 inches 
5. 15 
7.40 
20 inches 
10.12 
24 inches 
