22 BULLETIN 502^ U. S, DEPARTMENT OF AGRICULTUEE. 



joint siiiTOimded by cinders, gravel, or other suitable material. If, 

 in making turns or by reason of an irregularly shaped tile, a crack 

 one- fourth inch or more is left, it must be covered securely by broken 

 tile. All junctions at manholes and branches should be made securely. 

 Care must be exercised to prevent sediment from washing into the 

 tile, and when each drain is complete it should be free from sand, 

 mud, or other obstructions. 



The tile should be hauled and distributed along the line of trench 

 all in one operation. They should be hard-burned clay tile of good 

 quality, preferably in 2-foot lengths. They should have smooth 

 interior surfaces and should be hard burned entirely through, of 

 uniform texture, and free from lime or other impurities. No piece 

 should vary from a straight line more than one-half inch for a 2-foot 

 length. No tile should be used that has a piece broken from either 

 end deeper than 1^ inches. After the tile are laid they should be 

 covered carefully to a depth of at least 6 inches with broken shale, 

 gravel, or coarse cinders. 



Kelief wells can be installed with a 2-inch auger, or where hard 

 strata are encountered a churn drill can be used. Each well should 

 be located so that it. will come near the end of a tile ; it is then 

 connected with the line by chipping out one end of the tile with a 

 wrench, so as to leave a hole about 2 inches in diameter over the well. 

 All wells must be connected, regardless of whether they flow or not, 

 for they may flow later. 



Where the banks of the trench stand up well, the tile where .wells 

 are desired should be left with but little blinding over them; after 

 the line is completed a tile can be taken up at each of these places 

 and the well installed. In this case the wells can be placed directly 

 beneath the tile. In trenches where the banks will not stand, it 

 becomes necessary to drill the wells as the tile laying progresses, and 

 they should be placed a few inches to one side and connected with the 

 opening in the tile by placing a half tile over the well. They should 

 not be placed directly beneath the tile, for the sediment washing down 

 from the construction work above is apt to fill up the weak or non- 

 flowing wells. 



COST DATA. 



Where drainage systems have been installed wholly or in part by 

 the individual landowners, itemized records of expenses incurred 

 generally are not obtainable. However, it is believed that the tracts 

 from which the following data were obtained are fairly representa- 

 tive of conditions as ordinarily encountered in this type of drainage ; 

 consequently the unit costs may be assilmed to indicate fairly what 

 may be expected in excavating in this sort of material by hand 

 labor. 



