64 IRRIGATION FARMING. 



ninety cubic yards would be $4. 12, or 4.6 cents a cubic 

 yard. In handling sod four-horse plows are necessary 

 to break the surface. This material is very difficult to 

 handle, and the increased expense and small output 

 brings the cost up to five or more cents a cubic yard. 

 In heavy gumbo or cemented gravel, if plowable at all, 

 the cost of scraper work is generally increased to as 

 high as eight or even ten cents a cubic yard. As before 

 stated, in making canals the recently perfecfled graders 

 are more desirable than scrapers. These machines 

 consist of a plow which breaks up the surface, raises 

 the soil and throws it on an elevator, which delivers it 

 at the side of the ditch. The great amount of turn- 

 ing is avoided and the work is more rapidly done. 

 Dry sand is the most difficult material in operating 

 these graders, for, lacking adhesion, it does not rise 

 readily upon the mold-board of the plow and fall upon 

 the carrier. Experts, however, handle large quantities 

 in a day, and find the cost considerably less than 

 removing the same amount with scrapers. Fine dis- 

 integrated rock is equally as difficult to handle as sand. 

 Wet sand is more readily removed, as it holds together 

 better. These graders do good work in sod. In moist 

 clay or loam additional horse-power is necessary. 

 The same is true in adobe and gravel soils, but as the 

 machines are strong enough to stand a strain of twenty- 

 four horses, work can be done which is impossible un- 

 der any other method. 



The foregoing estimates cover ditches ranging from 

 2 feet wide at bottom, 8 feet at top, and 2 feet deep, to 

 16 feet wide at bottom, 32 feet at top, and 4^ feet 

 deep. Larger ditches can be built with the graders at 



