i66 



FARM DEVELOPMENT 



Drain tiles. Extensive experience in America has led 

 to the adoption of the cylindrical drain tile. In Figure 74 

 are shown drain tiles of the various sizes, from 2 inches 

 to 12 inches in diameter. Other forms have been recom- 

 mended at 

 various times, 

 but there is 

 apparently no 

 advantage of 

 these forms 

 over the cy- 

 lindrical, while 

 there are some 

 manifest disad- 

 vantages. 

 Straight tiles, 

 3 to 12 inches 

 in diameter, 

 are usually 

 made one foot 

 long, but occa- 

 sionally in two- 

 foot 



W 



429 FT. 



Figure 69. Map of drains. A simple plan of mapping to 

 record the location of a tile drain and its branches, giving the 

 lengths of the lines and the angles of divergence is shown 

 in this figure. The location of outlets and of the points of in- 

 tersection of tile drains may also be shown on a map by means 

 While 12 tO 2 A- of measurements from the sides of the farm or from other per- 

 manent points. In some cases it is practicable to mark an in- 



inrll ti1e<; are tersection of drains by a permanent monument, as by a large 

 c stone nearly buried. 



made in two- 

 foot lengths. Tiles with a shoulder (as shown in Figure 

 75), made like sewer pipes, are manufactured in two-foot 

 lengths, of all sizes. 



Drain tiles are made of clay similar to that used in 

 the manufacture of ordinary brick. The clay or mixture 

 of clay and sand must be of a nature to " burn " under 

 high heat in such a manner that when the tiles are 

 exposed to the action of moisture and frost, they will re- 

 main intact and not scale nor crumble. In nearly all 

 parts of America where drainage has been needed, clays 



