274 
give equal volumes of vapours, calculated by the expression 
, 
ele already given, the values of s and s’ being taken from 
s 
the third column. 
1 2. 3. 4, 
Specifie gravity 
at Boiling points 
referred to air 
Specific Gravity 
Weights, giving 
referred to air at 
equal volumes 
Boiling points. at 60°. of vapour. 
Water, 5)... 622 480 1.000 
Wood Spirit, 1.120 950 1.979 
Alcohol, . . 1.613 1.322 2.754 
Ether, i)... -2:586 2.397 4.993 
‘‘ It is now easy to assign the quantities of caloric necessary 
to produce an equal volume of the vapour of each liquid at 
their respective boiling points, for these will obviously be re- 
presented by the expression 
me {(t — 50) + 7} 
m being for each liquid its number in column 4, ¢ its specific 
heat, ¢ its boiling point, and / the latent heat of its vapour at 
the temperature of ebullition. When, with the aid of the an- 
nexed Table,— 
Boiling Points. Specific Heats. Latent Heats. 
Water, .. 212° 1.00 961.8 
Wood Spirit, 151.7 67 475.2 
Alcohol, . . 172.4 64 374.4 
Hither,: . . 1004 50 163.8 
which exhibits the specific and latent heats on which most re- 
liance can be placed, the numerical calculation is made, the 
following are the results: — 
WV RBC ath fees ty 1129 1.000 
Wood Spirit, . 764.8 676 
Alcohol, . . . 875.5 715 
thet tase ets 534.7 AT3 
