268 



Bulletin 254. 









sequent operation of filling the ditch. After any straw, etc., that may 

 be used is in place, the soil should be carefully thrown in by hand, avoid- 

 ing the dropping of stone on the tile with such force as to break them. 

 After enough soil has been thrown in and tramped to hold the tile in 

 place, the subsequent filling requires less care and may be performed 

 in a variety of ways according to circumstances. One method is the 

 use of the plow to which the horses are attached by means of a double 

 tree 9 or 10 feet long which permits them to walk in the clear on either 

 side of the excavation (Fig. 211). Another method is a form of 



broad scraper to which one or two 

 horses are attached. The scraper 

 is placed behind the excavated 

 earth and the horse stepped-up 

 until the earth is dumped into the 

 ditch when the horse is backed up 

 to repeat the operation. When 

 the horse becomes trained to the 

 operation, the process is a rapid 

 M one. Another rapid and convenient 

 method of filling the ditch after the 

 Fig. 210.— Filling the ditch. Shows fii'st covering of soil is in place is 



use of straw chaff or fine gravel used by H. E. Cook of Denmark, 

 immediately upon the tile to prevent ^ -i . . 



entrance of very fine sand and silt. ^ew York. i his is an ordinary 



wheel scraper or road machine 



similar to that shown in Fig. 216. The scraper is set well to one side 



and is a rapid method of filling where the machine and teams are 



available. 



(4) Sinks and silt basins. 



Where it is necessary to 

 admit a large amount of 

 water into the tile rapidly, 

 some more porous medium 

 than the soil must be used 

 and it must exclude the 

 entrance of soil to some 

 extent at least. That is, it 

 must have some filtering 

 capacity. The sink and filter 

 idea is usually combined. 

 One of the most common 



method used to admit water quickly to the tile is the stone sink. 

 Stone and boulders of difl'ercnt sizes arc filled in directly over the 

 tile and up as near to the surface as is necessary to meet the conditions. 

 In very heavy clay where it is undesirable to interfere with tillage, 

 the stone may only rise to the plow line. Under other conditions 



Fig. 211. — Shows use of the plozu in connec- 

 tion with a long double-tree to complete 

 the filling of ditch. 



