92 AGRICULTURAL ENGINEERING 



Cement tile are very satisfactory when properly made 

 and are of recognized quality. No attempt should be made 

 to make the tile porous, but as dense a mixture of cement as 

 it is possible to secure should be used. Where good coarse 

 sand is used, a mixture of 1 part cement to 2J^ parts of sand 

 has been used by the best manufacturers. A mixture con- 

 taining less cement will no doubt make good tile. Large 

 cement tile should be reinforced with steel. 



Fig. 58. Drain tile. Those at the left are of cement and those at the 



right are clay. 



In installing a drainage system, a careful inspection of the 

 tile should be made. All inferior tile which are soft, porous, 

 cracked, or overburned until of reduced size, should be 

 discarded. 



Laying Tile. Great care should be taken in laying the 

 tile. Small tile should be laid with the tile hook (See Fig. 

 59), but there is little doubt that the tile is laid more accu- 

 rately when laid by hand. Each length should be turned as 

 it is laid to secure the best fit. When a tile hook is used on 

 tile which are slightly curved, the bend of the tile is quite sure 

 to be up, leaving a larger crack at the top of the tile rather 



