SOIL HEAT 



299 



THE EFFECT OF SOIL MOISTURE ON THE VOLUME SPECIFIC 

 Hi; AT OF SOIL, THE MOISTURE BEING EXPRESSED AS A PER- 

 CENTAGE OF THE TOTAL WATER CAPACITY 



t ~ 





figg 



IM 



.6755 

 .8458 

 .9449 



Quartz 1.2919 

 Kaolin 



Humus .1647 



.3300 



.L'<)ir> 

 .2427 



.3682 

 .3558 

 .3207 



.4063 

 .4170 

 .3987 



.4445 

 .4783 

 .4767 



.4826 

 .5395 

 .5548 



.5208 

 .6008 

 .6328 



.5589 

 .6620 

 .7108 



.5972 

 .7233 



.7888 



.6353 

 .7812 

 .8669 



It is at once evident, from these data and the accom- 

 panying curves (see Fig. 46), that moisture, in its effect 

 on the specific heat of an average soil, is so potent as to 



1US 



To go 



30 4.0 



60 70 



60 



FIG. 40. C'virvti.s showing the effect of moisture on the volume specific 

 heat of soils of different texture and humus content. 



