Bench Construction 



ways, and of different materials. This tank is filled to about half an inch 

 above the sides with either specially constructed porous tile, or soft porous 

 brick, so arranged that there are numerous canals running between the 

 bricks over the bottom of the bench, so that when water is introduced into 

 the bottom of the tank it will rapidly spread by means of these canals over 

 the entire bench bottom. The bricks, or porous tile, will absorb this water 



Iron Bearer for Sub-Irrigation Bench 



rapidly, and pass it gradually upward through the soil, and in this manner 

 the water reaches the plants by means of capillary attraction and evapora- 

 tion. 



We have constructed a number of sub-irrigation benches upon the fol- 

 lowing plan : Yellow locust or red cedar posts from four inches in diameter are 

 used. The hole is dug to a depth of a little over two feet, and about six inches 

 of coarse grout, made of cement and clinkers, or broken stone, is thrown to 

 the bottom and thoroughly rammed. The post is then set in the desired 

 position, and the hole filled about half way with the coarse grouting, which 

 is rammed as the filling proceeds. The soil is then filled to the top. A 

 post set in this way is absolutely fixed, and there is no settling or moving. 

 The posts are about four feet apart from center to center, and upon the top of 

 these a yellow-pine bearer, six inches wide and two inches thick, running the 

 full length of the bench, is set on edge and firmly nailed. Into this bearer slots 

 are cut twenty-four inches apart, which are sufficiently wide and deep to hold 

 the tongue of a 2^-in. T-iron. These T-irons are cut 4 ft. 2 in. in length 

 for a 4 ft. 4 in. bench, and 4 ft. 6 in. for a 4 ft. 8 in. bench. Upon the end of 

 each iron is securely bolted a knee, as shown in the drawing. These irons are 

 placed in position, one iron in each slot. Then they are lined up so that the 

 iron knees will stand in a perfectly straight and regular row. These irons are 

 then securely nailed or screwed to the bearers. Terra cotta tiles, one inch in 

 thickness, seven inches wide, and twenty-four inches long, are now laid upon 

 the T-irons. The end of each tile will catch one and one-quarter inch upon 

 the iron. The sides of the tank are formed by angular tiles. (The shape of 



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