60 FIELD AND LABORATORY STUDIES OF SOILS 



This is because the amount of heat required to raise the 

 temperature of water is several times as great as that re- 

 quired to raise the temperature of soil. Consequently, 

 when any soil contains a large amount of water it is warmed 

 more slowly than a well-drained soil, which has been relieved 

 of its surplus moisture. 



