214 NOYES ON THE THEORY OF DISSOCIATION OF GASES. 
dissociation @ priori. It is with respect to the proof of this 
theory that I desire first of all to speak. Berthelot’s theory of an 
indefinite boiling point marches straight through every dynamical 
proposition connected with the theory of gases, and overturns 
amongst other things the fundamentally important law of 
Adagadro. 
The theory of dissociation assumes the decomposition of the 
molecules of a gas, whether this change is capable of chemical 
observation or not. As an example of a substance giving rise by 
two compartments by a diaphragm of porous earthenware placed 
at C. The part A C is connected with a continually working air 
as steam is introduced into C B, and by a suitable 
A arrangement is kept at a constant pressure 
whatever the temperature. Let the temperature 
acca Be on A a 
amount of gas coming through. But the amount 
of gas coming through will be proportional to the amount 
dissociated in C B. 
We require, therefore, to make a series of experiments at 
different temperatures in which the quantity of hydrogen or 
oxygen diffused through the plate per unit time is measured ry 
the ordinary processes of gas analysis, 
rom other experiments—simple in theory—but difficult in 
