352 



larger boulders, after having torn up and dislocated the 

 upper portion of the clays, in their passage along the sur- 

 face, may now be seen in prodigious numbers, and of the 

 greatest magnitude, lying up against the elevated range of 

 mountains to the south, whilst rare indeed is the circum- 

 stance to find a solitary fragment of any considerable size 

 any where along the intervening space. 



The various facts detailed in this communication, when 

 attentively considered, would appear to favor the hypo- 

 thesis advanced some years since, that by some powerful 

 convulsion of nature, the barrier was burst asunder which 

 pent up and confined the waters of this inland estuary or 

 arm of the sea, and caused an almost instantaneous drain- 

 age of the land. Such being the case, a violent rush or 

 current would be the result, sufficiently powerful to sweep 

 along at a rapid rate, even the largest of the boulders in 

 question, and by that means easily to disrupture the sur- 

 face of the clay, and produce all the effects that we at 

 present behold. But still, an adequate supply of water 

 seems to have remained, in order to evenly disseminate 

 the yellow sands over the irregular and broken up surface 

 long ere the land had become permanently dry. 



The following results of analysis have been carefully 

 obtained, expressly for this communication, by Dr. James 

 H. Salisbury, of this city. 



ELEMENTARY SUBSTANCES. 







I 



M 



III 



IS 



Silica, 



Chlorine,....: 



Total, 





esiso 6?!2( 

 i!44| o.'ej 



1.32 



0.24 

 6.92 

 1.80 



9. "88 



