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Mr. Desor referred to an account which he had given at 

 the meeting of December 4, 1850, of the Swamps existing 

 in the neighborhood of many western rivers. He stated 

 that he had received a letter bearing upon the subject from 

 M. Lesquereux, of Columbus, Ohio. By his request, Mr. 

 J. E. Cabot read a translation of it, which he had prepared, 

 as follows : — 



(Translation.) • 



Columbus, Decemher 12, 1850. 



. . . The fact you point out is not new ; indeed, it nearly 

 always occurs in the formation of peat-bogs, or indeed, of cedar 

 sivamps, which are the same thing. If you examined attentively 

 what you call the Jine sand of the banks of the river Monistic, 

 I think you must have observed that it is not a true sand, but 

 a loamy, (limoneiix,) argillaceous, impermeable alluvium. This 

 sand is found in all the peat-bogs of Europe ; in Switzerland, 

 in Germany, in Sweden, in Denmark, and in Holland ; every- 

 where it is the same. I have invariably found, on putting a 

 handful or two of this sand into a funnel, that it resisted the 

 passage of water to a really astonishing degree. But even sup- 

 posing your designation to be correct, and the sand of the Mo. 

 nistic to be really permeable, the following explanation is none 

 the less satisfactory. When a river overflows its banks, the 

 slimy sediment is deposited of course at the edge of the cur- 

 rent, and where its force ceases, and thus a ridge is formed 

 along the banks, behind which, on the retreat of the river or 

 stream, there remains stagnant water. This is the origin of 

 peat-bogs. The first growth of the still water is Chara, a plant 

 of a peculiar composition, containing a large quantity of sil- 

 ica, and to the decomposition of which I attribute in a great 

 measure the formation of the clay found in peat-bogs. The 

 idea of attributing a geological formation to vegetable decompo- 

 sition may seem to you at least extraordinary, but if I am able to 

 complete my work On the Infiuences of Vegetation, I hope to be 

 able to establish this and other facts at least as curious. Next 

 to the Char a comes the Sphagnum. To enable these plants to 

 grow, requires only a hollow in which moisture can lodge, and a 



