separatifiii of 

 the products 



proximatioas 

 merely. 



33^ COMl'OSITION OF SULPHURIC ETHEH. 



ThiJ, rcsidnum {hen must contain a considerable quant^v 

 of carbon, though the ether is more loaded ^vith it than the 

 alcohol. It will no doubt be remarked, that this residuum 

 contains oxigen and hidrogen nearly in the proportions that 

 - constitute Avater, or in that of 7 to 1. We must admit 



therefore, that 100 parts of ether arc nearly equal to 200 

 parts of alcohol, minus 28 parts of carbon, and 65 of 

 water, the formation of which has been occasioned by the 

 sujphuric acid. 



Not a perfect The black substance precipitated from the alcohol is not, 

 as has been said, pure carbon: nor does it appear, that the 

 liquid formed Avith the elements of alcohol by the sulphuric 

 acid is pure water. An imperfect separation of products 

 takes place here, as in all decompositions effected between 

 substances that have a very movable constitution, and little 

 disposition to solidity. 



The result ap- In this paper I have attained nothing farther than ap- 

 proximations, but in researches of so difficult a nature, 

 these results are the only ones we can expect. They can- 

 not acquire groat precision, but by repeated analyses suc- 

 cessively improved. 



Note on the Vapour of Ether, § VII, p. 327. 

 a paper read to the Society of Natural History and 

 Philosopliy at Geneva, December, 1804, I gave the parti^ 

 colars of an experiment made for the purpose of ascertain- 

 ing directly the specific gravity of the elastic vapour of ether 

 in vacuo. The conclusions drawn by de Laplace from the 

 observatiorts of Watt, my father, and Gay-Lussac, show 

 decidedly, that the elastic vapour of water is found in the 

 same quantity in vacuo and in the air at the same temper- 

 ature; but Me cannot apply the same law to ether, except 

 by analogy, or very indirect experiments. (See the expe- 

 riments of Mr. Dalton on the evaporation of ether. Man- 

 chester Memoirs, vol. V, or our Journal, vol. VI, p. 266.) 

 Experimentto I procured a matras, the body of which contained 30 

 ascertain that ^. j„(,]jgg ^nd the cylindrical neck of which was 32 

 of ethci". ' •' 



inches long, and about three lines in diameter. On, this 



neck I measured off a length of about two inches, and, 

 weighed the q;iantity of ether requisite to fill this length. 



The 



of elastic va 



JJOIUS, 



