140 IRRIGATION. 



verify his levels by turning the implement, and going 

 back over the line. 



Many rough, stony, or swampy pieces of ground already 

 in grass, may be improved without disturbing the sur- 

 face, by thoroughly draining the subsoil and laying out 

 j canals without reference to any particular line, but merely 

 causing them to follow the level in a direction meander- 

 ing to suit the surface. Hollows should be filled up with 

 earth taken from adjoining elevations, the sod being first 

 removed and then replaced. Waste pieces of land, at 

 present a refuge and nursery for weeds of many kinds, 

 and a detraction to the farms to which they belong, may 

 thus be changed at smaH cost into land of the most pro- 

 ductive kind. 



The irrigation of an irregular surface, such as hill sides, 

 although it may need more careful preparation and ad- 

 justment of the levels, is no more difficult than that of a 

 perfect level. In fact, there are advantages in favor of 

 the irregular surface which offset the apparently easier 

 irrigation of a dead level. Drainage is an indispensable 

 adjunct of irrigation, and no land is so frequently drained 

 by nature as a hill side, or what is known as rolling land. 

 Generally the simplest methods of surface drainage will 

 be sufficient for lands of considerable slope. The cost of 

 thorough underdraining is therefore saved in the case of 

 a meadow of this character. The water supply, and the 

 character of the canals suitable for irregular surfaces, 

 differ in no respect from those already described. It is 

 in the method of distributing the water, and laying out 

 the furrows, that especial directions are needed. 



There are several methods of irrigating lands of this 

 character, which are applicable to our circumstances. 

 Level furrows may be used by which the water is carried 

 in winding directions around the elevations and depres- 

 sions of the surface, from feeders which are taken from 

 the main supply canal whenever it may be most con- 



