RELATIONS OF SOIL TO WATER 



blocks of soil have the respective depths of 20, 40, and 60 

 inches; the surface area of the soil is in all cases T^Voth. of 

 an acre. The soil is a heavy loam containing many flints, 

 having a clay subsoil. The surface of the soil is kept free 

 from weeds, and undergoes no tillage. 



The average amounts of monthly percolation during twenty 

 years, as shown by the shallowest and deepest soil of the 

 Rothamsted drain-gauges, will be found in Table XIV. Further 

 results from these and other drain-gauges will be found on 

 pp. 109, 122. 



TABLE XIV 



AVERAGE MONTHLY PEKCOLATION THROUGH BARE SOILS 



TWENTY INCHES AND SIXTY INCHES DEEP, 



ROTHAMSTED 



As the amount of evaporation from the soil is far greater 

 in summer than in winter, the amount of drainage naturally 



