Snaier.] 284 [March I, 



of the occurrence of materials containing phosphoric acid in some of 

 its combinations. 



The tolerably uniform dissemination of phosphate of lime through 

 the marl beneath the phosphates cannot be explained on any theory of 

 the formation of such deposits that has come under my observation. 

 The general character of the marl underlying the phosphates is quite 

 different from what would be supposed from the fact that it contains 

 numerous vertebrate remains. It does not seem to have been a de- 

 posit formed near the shore, but rather to have been the product of 

 those agents of deposition which work in the deeper parts of the sea. 

 It was my good fortune to see some of the material brought up from 

 the floor of the Gulf Stream between Florida and Cuba, from a depth 

 of nearly two hundred fathoms; the resemblance of the general char- 

 acter of this material to the marls beneath the phosphate bed is quite 

 striking. It is by no means improbable that at the time when these 

 beds beneath the phosphate bed were being accumulated, the Gulf 

 Stream flowed over them. The peninsula of Florida did not then 

 exist, and the natural path of the stream must have been just over 

 the region of the Ashley River beds. 



The material brought up by the Coast Survey dredging work un- 

 der the direction of Count Pourtales, consisting, as has just been 

 stated, of a marly substance, resembling in a general way the marls 

 of the Ashley and Cooper Rivers, has recently been subjected to 

 analysis, and strange to relate, it, too, contains a considerable amount 

 of phosphoric acid. The analyses are not yet complete, but will in 

 due time be made public by the officer having these dredgings in 

 charge; but enough is known to make it sure that the chemical 

 character of the material now accumulating on the bottom of the 

 Gulf Stream, is likely to show a surprising likeness to that wdiich was 

 laid down on the sea floor where the Ashley and Cooper Rivers' beds 

 were formed. 



It is not the least singular part of the likeness of the materials on 

 the Gulf Stream floor to the beds beneath the phosphates, that there, 

 too, vertebrate remains abound. The dredge of Count Pourtales 

 brought up from the bottom of the stream a considerable number of 

 fragments of the bones of the dugong, or some allied animal. It 

 might at first sight seem as if the occurrence of these bones afforded 

 a sufficient explanation of the presence of phosphoric acid in the 

 material composing the floor of the Gulf Stream, but here, as on the 

 Ashley and Cooper River marls, it would be necessary to suppose 



