180 SOILS: PROPERTIES AND MANAGEMENT 



The relationships already spoken of are especially well 

 shown by the curves (see Fig. 26), particularly the effect 

 of the moisture content on cohesion. In a heavy soil the 

 cohesion increases steadily from a saturated condition until 

 dryness is reached, the increase becoming accelerated as 

 the percentage of moisture decreases. This is because 



Fig. 27. — The cohesion curves of clay and fine sandy loam at various 

 moisture contents. (C), point at which soil changes in color. 



