S. p. Sharpies on Dredgings from the Gulf Stream. 



Art. XXY.— Contributions from the Laboratory of the Lawrence 

 Scientific School Ho. IS.— On some rocks and other dredgings 

 from the Gulf Stream ; hy S. P. Sharples, S.B. 



Some time ago Mr. Pourtales gave me for analysis some spe- 

 cimens of bone, rock, and ooze obtained from the bed of the 

 Co-ult btream between Florida and Cuba, while dredging under 

 the du-ection of the Superintendent of the U. S. Coast Sinvey. 



ihe bone was a piece of the rib of the Manatee. For com- 

 parison with this Mr. Pourtales obtained a piece of the same 

 bone from the skeleton in the Museum of the Boston Natural 

 Mistorj Society. He also furnished me with a number of 

 spmmens of coral from the adjacent shores. 

 *i, \ v Pf "sptonc acid was determined in every case, except 

 that oi the fresh bone, by means of ammonic molybdata In 

 tne tresh bone it was determined by Eose's method with mer- 

 cury. Before treatment with the molybdate the specimen was 

 m every case submitted to the action' of the blast lamp for fif- 

 teen or twenty minutes in a platinum crucible ; by this means 

 peS ^^^^ organic matter and carbonic dioxide was ex- 



The first analysis was that of the bone ; it was dark colored 

 and almost destitute of organic matter, but still showed distinct 

 traces ol fibrous structure. Its density was much greater than 

 iresi bone and it had become very hard. It was fromtte 

 ™gj^g «f May 9, 1868, in 106 fathoms. By the side of it is 

 placed the analysis of the recent bone, which is also calculated 

 as tree from organic matter. 



^-J^k), 1^60 ''''' '!'' 



J.^^'Og, 26-47 4-52 7-21 



S1O2, .3^ 



Ha 0-4- organic, 2-67 36'69 



r^ 9R7 9£m 100-00 



roft L^^^?^"^ specimen examined was a hard dark colored 

 in 100 ?^i, dredging of May 15, 1868, off Sand Key, Flonda, 



1 w lathoms. It was nearly free from organic matter, 

 tained ^Z 'P^^^"^^^ ^^s similar to No. 2? except that it con- 

 shell a^H ^T^^«, matter and was intermixed with broken 

 tion Ttl'^^'i' ^°^. ^PP^^^^d to be of a more recent form " 

 -g in 116 f"t\om? '''' ^''^^""^ °' ^^^ ^^^' ^^'^' ''^' ^ '■ 

 seem'in^l J'^f i5 l^^^^^'^^ck made up of fragments of corals and 

 seemingly held together by calcic carbolate; it was nearly 



