286 EXPERIMENTS IN DRAINING. 



except that in two or three places they became ob- 

 structed by sand and gravel that had washed down 

 by the current of water and filled the tile. These 

 obstructions, however, were much more readily dis- 

 covered and more easily removed than those in the 

 stone drains. In the spring of 1850 I purchased the 

 pipes or round tiles, and during the season con- 

 structed 1,350 rods of drain, and in 1851 I laid 

 1,240 rods ; and for the purpose of giving a more 

 definite idea of the form of their construction, I here- 

 with annex a diagram, as near as may be, (without 

 claiming to be precise,) of the drains laid in two 

 fields, one of which was laid in 1850, and the other 

 in 1851. The drains are made 2$ feet deep, and 

 whenever we find a slight elevation extending a 

 short distance only it is made deeper in order to 

 have the inclination of the bottom as even as possi- 

 ble, so that they average something more than 2 4 

 feet deep. Having the drains thus opened and the 

 tiles being distributed along the bank, they are laid 

 in by a man, who, commencing at the upper end 

 of the ditch, walks backward down the same, placing 

 the tiles in their places as he goes, which may be 

 done very rapidly, a good hand laying at the rate of 

 500 or 600 rods per day; being sure they lie in a firm 

 immovable position, then place a small quantity 



