Association of American Geologists and Naturalists. 131 



Afternoon^ A.^ o^ clocks P. M. — Dr. Charles G. Page exhibit- 

 ed two new electro-magnetic instruments, of his invention, to pro- 

 duce a reciprocal motion. He calls it the axial reciprocating en- 

 gine. 



Dr. P. also made an oral communication on injecting the Lepi- 

 doptera with oxalic acid, to produce instant death without injury 

 to the plumage, by using a small glass tube drawn to a fine point, 

 piercing them under the thorax. He also recommended to de- 

 stroy the grease of the insect by the use of bibulous paper, touch- 

 ing the insect underneath, and in contact with the lining of the 

 cabinet case. 



Mr. James Hall remarked on a supposed incorrectness of Dr. 

 King's outline of the coal field in Missouri. 



Pi'of. H. D. Rogers thought that the sandstone called by Dr. 

 King carboniferous, is the Waverley sandstone of Ohio ; and Dr. 

 Troost, in his last (seventh) annual report, corrects the statement 

 in his fifth report that it was the carboniferous. 



Dr. J. L. Smith made a communication on the existence of the 

 oxide of cobalt near Silver Bluff, South Carolina. The manner in 

 which the oxide occurs is on the surface of a coarse gravel, and 

 was first made known to Dr. Smith by Prof. Ellet. The oxide is 

 associated with the oxide of manganese, and is free from arsenic. 

 The analysis of the mixture of the oxides does not give constant 

 results. The result of one analysis was 35 per cent, of oxide of 

 cobalt, and 65 per cent, of oxide of manganese. 



He also made a, communication on the composition of fossil 

 bones. Some remarks on the recent analyses of MM. Girardin 

 and Preisser were made. The cause of the presence of fluorine in 

 these bones was particularly discussed, with a view to show that 

 the above mentioned gentlemen were mistaken in their idea that 

 fluorine was infiltrated in the bones after the death of the animaL 

 The principal argument was, that an analysis of two bones taken 

 from the same locality, gave less fluorine in those bones where it 

 was evident that most foreign matter had been infiltrated. 



Lieut. Maury, U. S. Navy, read a paper on ''the Currents of 

 the Sea as connected with Geology," with a chart of the north 

 Atlantic Ocean. Many of Lieut. M.'s remarks will be found in 

 his interesting paper on the Gulf Stream at p. 161 of this No. 



Prof. H. D. Rogers remarked on the importance of the sub- 

 ject presented by Lieut. Maury, and suggested the appointment 



