60 IRRIGATION' FARMING. 



oughly in place, and then the coating of Portland or hy- 

 draulic cement is put on with a thickness of three-quar- 

 ters of an inch. It has been- found that this layer is 

 durable and abundantly able to withstand all the strain 

 that will be put upon it. The cement is mixed with 

 clean sand in the proportion of one barrel of the former 

 to four barrels of the latter. For a canal carrying 3500 

 cubic inches of water, with a bottom eight feet wide and 

 sides four feet high, it requires 2000 barrels of cement 

 for seven miles of length. The work of laying the ce- 

 ment is done very rapidly and thoroughly. Along the 

 edge of the canal a small pipe is laid, through which a 

 steam pump forces the water which is used in keeping 

 the earth wet and in mixing the mortar. At regular in- 

 tervals are placed piles of sand and barrels of cement. A 

 mixing box on wheels with a trough running down into 

 the canal is run on the top of the bunk, and the plasterers 

 take from this and cement the sides. This is moved 

 along as fast as needed, thus saving the use of wheel- 

 barrows. Following comes another mixing box on 

 wheels in the bottom of the canal and from this the 

 mortar is taken to cement the bottom. The work should 

 be allowed to stand for a time so as to thoroughly dry 

 before water is turned in. 



Building the Laterals. In constructing the 

 supply laterals leading from tho main, canal to the farm, 

 the walls should.be built up so that the bottom of the 

 lateral may be higher than the surface of the ground. 

 This is vital to the economic use of water. The laterals can 

 be constructed in the loose soil on the farm for the r< 

 that the water is desired to soak into the ground. The 

 laterals may be changed every time water is put on the 

 land, for the reason that always as soon as possible aft'-r 

 irrigating, the ground should be cultivated, thus obi iter- 

 ating the lateral and preventing the soil from baking. 

 There is nothing so good in the long run for building 



