Diluvium. 141 



detailed. This subject, however, I shall examine more particularly 

 farther on. 



"Valleys in other parts of the State. 



The remarkable and interesting- valleys in Berkshire county, de- 

 serve long and careful study. After having passed across them and 

 through them several times, my decided conviction is, that for the 

 most part, they are primary valleys which have been more or less 

 modified by deluges and other abrading agencies. The valleys in 

 Worcester county seem to me to have had a similar origin ; and I 

 may add also the valley of the Merrimack. I mean that the original 

 elevation of the strata gave to these valleys their great outlines. And 

 the general parallelism of most of these valleys, agreeing also with 

 that of the Connecticut, seems to indicate that nearly all the great 

 valleys of Massachusetts were produced at the same epoch. But I 

 hope to render this subject more intelligible when I come to treat of 

 the systems of elevation that are found in our strata. 



If it should seem that I have been very prolix in discussing the 

 subject of Alluvium, I beg it may be recollected that it is one which 

 excites at present an absorbing interest among geologists ; and that 

 scarcely no efforts have been made in this country to exhibit the dy- 

 namics of causes now in action. I hope this fact will afford me an 

 apology for the imperfection of this effort. 



2. DILUVIUM. 



Under this term I include that coating of gravel, bowlders, sand, 

 and loam, which is spread over almost every part of the surface, and 

 which has been obviously mingled confusedly together by powerful 

 currents of water. Hence geologists have referred it to the agency 

 of a general deluge ; and since it occupies the highest place in the 

 rock series, except alluvial and volcanic rocks, most of them have re- 

 garded that deluge as identical with the one described in the Chris- 

 tian Scriptures. But recently some respectable geologists maintain, 

 that existing causes, operating as they now do, might, in the course 

 of ages, have produced all the phenomena of the rock formations. 

 Hence they deny the existence of such a deposit as diluvium ; or r 

 rather, they impute it to rivers, rains, frost, and other existing agen- 

 cies, and include it under alluvium. Others, however, regard dilu- 



