476 Dr. Ure on the ultimate analysis of 
And in volumes, 3 olefiant gas = .9722 x 3 = 2.9166 
4 aqueous vapour = . 625x4 = 2.500 
Thus alcohol of 0.812, by the above analysis, which I be- 
lieve merits confidence, from the care and consistency of the 
experiments, differs from M. Gay Lussac’s view of absolute 
alcohol, deduced from M. Th. de Saussure’s experiments, 
in containing an additional volume of aqueous vapour. At 
the specific gravity .814 alcohol would have exactly this 
atomic constitution. If the condensation be equal to the 
whole 3 volumes of olefiant gas, that is if the 7 volumes of 
constituent gases become 4 of alcohol vapour, we shall have 
its specific gravity at this strength = 1.3722 ; the additional 
volume of aqueous vapour producing necessarily this abate- 
ment in the density. 
We have already considered sulphuric ether. 
The next 4 bodies which occur in the table are of fibrous 
texture, and are chemically characterized by an excess of 
oxygen beyond the hydrogen equivalent. 
Fibres of the bleached threads of the silk-worm were sub- 
jected to analysis. Their composition is apparently, 
Carbon 10 atoms . . 7.5 . . 50.8 
Hydrogen 4 . .0.5 ... 3.4 
Oxygen 5 . . 5.0 . . 34.0 
Azote . 1 . . 1.75 . .21.8 
14.75 100.0 
or, 4 of olefiant gas, 5 of carbonic oxide, and 1 of nitrous 
oxide ; or of 1 atom prussic acid, 3 atoms olefiant gas, and 
5 atoms carbonic oxide. 
