4 .66 Dr. Ure on the ultimate analysis oj 
a great number, seem to consist of 
Carbon 0.8345 
Hydrogen 0.1318 
Water 0.4337 
1.4000 
And in 1 grain we shall have 
Carbon 0.5960 3 atoms 2.25 60.00 
Hydrogen 0.1330 4 atoms 0.50 *3-33 
Oxygen 0.2710 1 atom 1.00 26.66 
1.0000 3.75 100.0 
Or, 3 volumes olefiant gas = 3 x 0.9722 = 2.9166 
2 . . vapour of water . 2 x 0.625 — 1-25 
4.1666 
which suffering a condensation equal to the whole vapour 
of water, will give an ethereous vapour, whose specific gra- 
vity is 2.5. 
The proportion of the constituents of sulphuric ether, de- 
duced by M. Gay Lussac from the experiments of M. Th. 
de Saussure, are 2 volumes olefiant gas -|- 1 volume vapour 
of water, which 3 volumes are condensed into 1 of vapour of 
ether, having a specific gravity = 2.58. The ether which I 
used had been first distilled off dry carbonate of potash, and 
then digested on dry muriate of lime, from which it was 
simply decanted, according to the injunction of M. de 
Saussure. Whether my ether contained more aqueous 
matter than that employed by the Genevese philosopher, or 
whether the difference of result is to be ascribed to the dif- 
ference in the mode of analysis, must be decided by future 
researches. 
