157 



bomes more difficult; as it is necessary 

 that the sides of the ditch, which conveys 

 the water for distribution, should be raised 

 all that distance, and kept high enough to- 

 caiTy the water to the aforesaid highest 

 part. In this case cut, in as direct a lino^ 

 as circumstances will allow, a wide ditch, 

 or master-feeder, keeping up its banks, 

 not upon a dead level, but with a gradual 

 descent from beginning to end. Sup-i 

 posing, for instance, the highest part oh 

 the meadow to be one hundred yards dis-^ 

 tant from the stream, and you have five 

 inches fall in that distance, you are to 

 give to the whole length ah equal degree 

 of deseenti that is, to each twenty yards^ 

 one inch fall, and then every drop of watei* » 

 will be kept in equable and constant 

 motion. 



. Sometimes the land has a very uneven 

 A X suiface. 



