1890.] PUBLIC DOCUMENT— No. 4. 295 



SOILS OF MASSACHUSETTS. 



BY PROF. N. S. SHALEK OF CAMBRIDGE. 



Although the soils of Massachusetts belong altogether 

 to the group which we may term exotic, — that is, wliere 

 the materials composing them are not derived from the 

 underlying rock, but are transported from a distance, — 

 they exhibit a considerable range of phenomena, and are 

 interesting both from a scientific and economic point of 

 view. In the following account of the soils of this Common- 

 wealth, I propose to consider first the origin and range of 

 their character, and the relation of their characteristics to the 

 geological history of the region ; second, the relations of 

 these deposits to the actions occurring during and after the 

 glacial period ; third, the present physical condition of 

 these soils, and the economic aspects of the deposits. 



The soils of Massachusetts, and indeed of all parts 

 of New Enghmd, are of glacial origin. Practically the 

 whole of the detrital material which composes them was 

 rent from the bed rocks l)y the action of the ice sheet. 

 Here and there the post-glacial decay has stripped small 

 portions of the detritus from the Underlying rocks, and com- 

 mingled it with the soil. But these areas are in all cases 

 insignificant in extent, and do not serve in any important 

 way to qualify the character of the detrital materials which 

 have been formed by glacial action. 



Where soils are formed by glacial action, they differ 

 essentially from those which are produced by ordinary agents 

 of decay. Non-glacial soils, such as cover the larger por- 

 tion of the earth's surface, are mainly formed by corrosive 

 action, by the processes of chemical decay through which 



