352 



Irrigation and Drainage 



of strong plank, set at an angle and shod with steel, 

 as shown. This tool is much used in France and 

 Italy, and a modification of it we saw in use at 

 Grand Junction, Colorado, where a pair of low wheels 



Fig. 91. Simple land grader. 



were attached to the front of the scraper on a bent 

 iron axle, which could be worked by means of a lever 

 to raise or lower the scraper at will, thus causing it 

 to drop or take on dirt where desired. 



FIELD IRRIGATION BY FURROWS 



Where crops like maize, sorghum and potatoes are 

 grown in large fields, and where infertillage must be 

 practiced, it is usually best to irrigate by the furrow 

 method after the crop is on the ground. In countries 



