CONSTRUCTION 141 



183. Correcting depth. If at any point too much 

 earth is removed and the ditch made too deep thereby, a 

 sufficient amount must be returned and carefully molded 

 into place with the scoop, to bring the bottom up to grade. 

 The less the fall, the greater is the care that must be 

 exercised in finishing the bottom. This part of the work 

 is not difficult, although it requires care and judgment. 

 It is sometimes done from the surface. Usually, how- 

 ever, the workman stands in the ditch. 



FIG. 56. End section of ditch, showing in diagram the bottom of ditch 

 formed to receive the tile. Note the width of the top of the ditch 

 as compared with the 12-inch length of tile resting on its edges. 



184. Laying the tile. The laying of the tile should 

 begin at the outlet and proceed toward the upper end. It 

 is usually best to lay the sections of tile as rapidly as the 

 bottom of the ditch is made ready with the tile scoop to 

 receive them. Some workmen lay the tile by hand and 

 some use the tile hook; some stand upon the surface to 

 finish the bottom of the ditch and to lay the tile. 



185. Making close joints. It will be found that the 

 ends of the tile are frequently not square, are not at 

 right angles to the sides, and that the tile is sometimes 

 warped, or bowed, thus throwing the ends out of square. 

 There are sometimes little inequalities in the bottom of 



