not needed, this implement gives remarkable results. If the roller is 

 run at right angles to the prevailing wind, it prevents, in a great meas- 

 ure, the soil from blowing. The hollow spaces between the ridges, 

 which are from one to one and a half inches deep, contain dead air and 

 the current of dead air above holds it in place and supports the edges, 

 on the same principle that water in a little bayou on the border of a 

 swift stream is always still, held as it is in place by the pressure of the 

 stream. This feature alone is of great value in windy sections. 



Third, the fluted shape of the wheel so pulverizes the soil that a 

 mulch is formed which prevents rapid evaporation of moisture. The 

 implement is used to good advantage on gi^ain after it is up. The soil 

 is made compact about the roots and the mulch prevents the escape of 

 moisture. 



Storing Water 



Farm crops require water, and without it they will not grow. It 

 requires 300 pounds of water to make one pound of dry matter, or from 

 400 to 700 tons to mature an acre of cereals, corn, hay or root crops. 



In semi-arid regions where the rainfall is from ten to eighteen inches 

 and the greater portion of that during the winter and early spring, 

 it becomes necessary to store the water in the subsoils to be utilized 

 during the summer or growing season. It is not uncommon to produce 

 a good crop without rain during the entire growing season, if care is 

 giving to storing and conserving moisture. 



No fast rules can be laid down regarding the amount of water which 

 can be stored in the soil. The amount depends, 1st on the amount of 

 rainfall, 2d on the physical condition of the soil, 3d on its holding 

 power; 4th on the amount of evaporation due to heat and wind; 5th 

 upon the surface tillage or the vegetable growth. 



The irrigating farmer floods his land, thereby furnishing moisture 

 from the surface. The humid-section farmer depends on occasional 

 showers to make his crop, and the dry farmer irrigates from below 

 upwards. 



The dry-land farmer who fails to store water in the subsoils is in 

 the same predicament as the irrigating farmer who fails to fill his 

 reservoir. If the supply is inadequate in either case during one sea- 

 son, they must wait until a sufficient amount is provided. The irriga- 

 tor waits until his reservior is replenished, the other summer-fallows. 



Water obeys the law of .gravitation. When it strikes the surface 

 it follows the course of least resistance. If the surface is porous the 

 water soaks in rapidly, but if it is hard and impervious, it runs away 

 or is lost by evaporation. If the porous condition is eight or nine inches 

 deep, it will take care of two or three inches of rainfall, but if it is 

 shallow, as soon as the porous stratum is filled, the surplus is lost. 

 Hence, the necessity of at all times maintaining a depth and porous 



