CONSERVATION OF SOIL MOISTURE 



the sub-soil by means of surface tension. 

 Thus, when the sun is hot, or a drying 

 wind scorches the ground, the soil 

 moisture rises — as oil is drawn up to 

 feed the flame of a lamp- wick — from 

 the water-table below, which may be two, 

 six, or twenty feet beneath the surface of 

 the ground; that is, wherever free or 

 standing water is found. Hall mentions 

 the steady rise of capUlary moisture 

 through 200 feet of fine-grained chalk 

 during a dry season in the south of Eng- 

 land. 



Furthermore, capillary action depends 

 on the fineness of the soil particles and 

 their closeness to each other. In coarse, 

 loose, sandy, or gravelly soils the action is 

 weak; in fine, well-compacted soils it is 

 strong. Thus in the conservation of soil 

 moisture capillarity is a matter of the ut- 

 most importance; and, accordingly, in 

 selecting a farm or a portion of a farm 

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