166 EXPERIMENTS ON THE SPECIFIC 
When due allowance is made for water con- 
tained in alcohol of this specific gravity, 100 
cubic inches will weigh 53.8 grains, tempera- 
ture 60° and pressure 30 inches mercury, and 
when the deduction is made for the expansion 
of glass and mercury, it will give the weight for 
100 cubic inches at 60° temperature and 30 in- 
ches pressure 46.30 grains, and specific gra- 
vity of the vapour 1.49, atmospheric air being 
1. If we take a mean between Dr. Dalton’s and 
Dr. Thomson’s weight of hydrogen the vapour 
of pure alcohol will be 23.1 times hydrogen. 
VAPOUR OF ETHER. 
The 42 inch tube was used in these experi- 
ments :-— 
Capacity of the tube 4.64 cubic inches, 
ball 3.46 “ 3 
together 8.1 “ 2 
Specific gravity of the ether .728. 1.8 grains 
in measure being equal to 1.31 grains in weight, 
were sent up. 
