THE SUBSOIL. 

 TABLE F. 



75 



In examining all soils, we find that they consist 

 of two layers, or strata, of varying thickness. The 

 npper or surface soil is of a darker color than that 

 which underlies it, because it possesses the organic 

 remains of vegetable matter. Sometimes it is only 

 three or four inches in depth, although in many 

 fertile lands it may be found to as many feet. 

 Beneath this lies the inferior layer, or subsoil. 

 M. Boussingault, in the translation by W. Law, 

 says : 



" In plains, on high table-lands, the analogy, in 

 point of constitution, between the soil and subsoil 

 is not so constant as in some other places. In such 

 situations the arable land is frequently an alluvial 

 deposit, proceeding from the destruction or disinte- 

 gration of rocks situated at a great distance. When 

 the superior strata possesses properties that are 



