respecting the Mixture of Gases, Sc. 323 
Cor. 1.— When the volumes before mixture are equal 
EF i 2 S 
ae =p; or the resulting elastic force is the mean be- 
tween the elastic forces before mixture. 
Cor. 2.—If F =f, then F = p, or the elastic force, is not 
changed by mixture. eae. 
ProposiTionIIJ.—If given volumesV, v, of gases or vapours 
of different elastic forces F, f, be mixed, and the elastic force 
c VF J 
of the mixture be p, then aie = the volume of the mix- 
ture. 
~ For, by Prop. 1, the elastic force of each gas is to be equal 
to the elastic force of the mixture, and therefore 
ite VF 
ae eens Vs -- = the volume of the gas whose force be- 
P 
fore mixture was F; and 
Tank 
ra 5 39: af = ‘the volume of the gas whose force was f 
before mixture: hence, the volume of the resulting compound 
, Veto 
Pp 
Cor.— When V = », and F = p, we have 
ee = the volume after mixture. 
This condition, viz. that V = v, seems to apply with accuracy 
to the combination of air with the vapour of water, when the 
Vp 
Pia 
the volume; and to put the two to the test, let an experiment 
be made when / is equal to 3 p. 
By Mr. Dalton’s formula, the volume of the mixture of air 
and vapour would be three times the volume of the dry air. 
By my formula the volume of the mixture of air.and vapour 
would be only 13 of the volume of the dry air. 
I did intend to conclude here; but I cannot resist the temp- 
tation to ask Mr. Dalton, or M. Gay-Lussac, how in a mix- 
ture of one part of dry air of an elastic force of 30 inches of 
mercury with 2 parts of vapour of the elastic force of only 
20 inches, the whole mixture should possess an elastic force 
of 30 inches? If they can answer this question satisfactorily, 
we need not altogether despair of a perpetual motion being 
discovered. But to be once again serious: I shall be very 
happy to have any error in my train of reasoning or results 
pointed out, should such be detected by any of your learned 
contributors. 
16, Grove Place, Lisson Grove, May 2, 1826, 
282 L. On 
air is saturated. Mr. Dalton arrives at the formula 
