142 CAMPBELL'S SOIL CULTURE MANUAL 



heading of " Evaporation," we have given the results of 

 some experiments by Professor F. H. King of Wisconsin 

 showing; the rapidity with which moisture \\ill rise through 

 the soil by what is known as capillary attraction, reach 

 the surface and pass off in vapor into the atmosphere in 

 a single day. Not until the farmer begins to grasp the 

 vital importance of keeping even a little additional water 

 in his soil can he be expected to use all diligence due in 

 preventing this evaporation. This observation of the 

 farmers throughout the semi-arid west, during the grow 

 ing season of 1901, especially Kansas and Nebraska, 

 ought to be amply convincing with reference to the value 

 of stored water in the soil. There were frequent remarks 

 during its prolonged and severe drouth of the mid-surnmer 

 with reference to how the corn continued day after day 

 and week after week, contending against this extreme 

 heat without rain, without showing any apparent effect 

 of drouth; but this was simply the direct result of the 

 unusually heavy rains in early spring that percolated 

 down into the soil, in many instances eighteen inches to 

 two feet deeper than usual, and there acting as a reserve, 

 continued to return by capillary attraction and feed the 

 corn plants and other grain until it was exhausted. In 

 this same chapter on evaporation we make mention of 

 seyeral instances where the early disking of the ground 

 resulted in retaining a sufficient amount of additional 

 water to carry a crop of corn through, increasing its yield 

 in some instances as high as twenty bushels, which was 

 not secured in adjoining fields, not disked, simply because 

 the moisture was allowed to evaporate by leaving the sur- 

 face hard and compact, as is always the condition after a 

 heavy rain or snow. 



