Account of an Examination of Fused Charcoal. 467 



covery of a method of rendering die cornea transparent. — M. 

 le Baron Blein communicated a new Memoir on Colours. — M. 

 Gay-Lussac gave an account of an experiment relative to Mad. 

 Gervais's apparatus, which proved that a very small quantity 

 only of volatilized wine could be collected by its means. — L 

 M. Latreille read a note on a new genus of Spider, which he 

 has named Myrmecia. — M. Yvart made a verbal report on 

 the Agricultural Annals of Roville, published by M. Dom- 

 basles. A report was received from M. Bosc, on a species of 

 Leech found at Martinique ; and another from M. Cauchy, on 

 the mathematical researches of Professor Simonoff of Casan. 



LXXXIII. Intelligence and Miscclla?icous Articles. 



ACCOUNT OF AN EXAMINATION OF FUSED CHARCOAL. 

 BY LARDNEE VANUXEJI. 



HPHE specimen examined was sent to Dr. Cooper by Pro- 

 ■*- lessor Macneven of New York, who obtained it by means 

 of the deflagrator invented by Dr. Hare. 



Dr. Cooper was so good as to present me with the fused 

 charcoal, knowing that I was extremely desirous of experi- 

 menting upon it, being very sceptical as to its resulting from 

 the fusion of the carbonaceous part of the charcoal, believing 

 on the contrary that it was little else than the metallic, earthy, 

 saline, or alkaline materials, probably enveloping charcoal in 

 the black globules, or if iron were present, combined with that 

 metal, constituting a product analogous to steel. 



My opinion that the fused charcoal in question was derived 

 from the impurities of the charcoal, was principally owing 

 to the sources of error not having been removed ; and that 

 these sources are very considerable, is well known, not only to 

 those who have been engaged in the analyses of the different 

 kinds of our ordinary combustible substances, but is obvious 

 to the common observer, by the quantity of ashes which is 

 left, when wood or coal has been incinerated. 



Dr. Macneven did not mention that he made any experiment 

 upon the fused charcoal, other than that of ascertaining its 

 comparative density with sulphuric acid, in which liquor it 

 sunk. 



The fused charcoal consisted of one large, and one small 

 globule, connected together by a thread, or thin bar of the 

 sa material, and resenibled a double-headed shot ; exter- 

 nally its colour was black and without lustre, and was per- 

 fectly opaque. It weighed L i'o centigrammes, or 0*385 of a 

 grain. 



9 N 2 In 



