528 On the two great powers, . [Ocr. 
might be true, it is evidently necessary, that repulsion be supposed to 
vary in the same, or a less, inverse ratio of the distance, than the at- 
traction ; either of which has beenabove proved impossible. 
Another author of great merit appears to have written with the same 
impression. Mr. Daxron argued against BerTHOLLET, that if the mix- 
ture of gases depended on an attraction exerted between them, they 
ought to enter into perfect combination*. This is a just objection, if 
repulsion be supposed to vary in the same, or a less, inverse ratio of the ~ 
distance, than the attraction. And neither BerTHoLLeT, nor Dr. Mour- 
RAY, had shewn, that either of these suppositions is impossible ; nor 
did they answer this objection of Mr. Datron’s as if they were 
aware, that the two forces could not vary in the same ratio. 
Again, in explaining the nature of mixed gases, Mr. Datron (as 
has been already observed) considered the attraction, and force of re- 
pulsion, between the atoms of the fluids so nearly equal, that neither 
force affected the mixture at allt. But then it is necessary to suppose 
(to the end that neither may affect the mixture of the gases) in addi- 
tion to the two forces being equal, that they should also vary in the 
same ratio. 
For, did they not, one of these forces beyond, or within a certain 
point, becoming the greater of the two, must operate}. 
It would be easy to shew, by quotations from all authors, that none 
have hitherto pursued the inquiry spoken of above ; but it is sufficient 
to have proved this fact, from the writings of two of the ablest philo- 
sophers. 
After having maturely considered the various doctrines, and theo- 
ries, which are taught in the statics of chemistry ; I became persuaded, 
that several of them were far from satisfactory ; among them in parti- 
cular, the doctrines, upon which I have been remarking. And while 
endeavouring to investigate the cause of their insufficiency, an expla- 
nation presented itself to me, which appeared free from all the difficul- 
ties, and objections, to which former theories are liable ; and which 
will account for the permanency of all states, and combinations of 
bodies; namely,— 
That the force of repulsion, with which heat endows atoms, varies 
an a greater inverse ratio of the distance than their attraction. 
* Manchester Memoirs, vol. v. part 2. 
+ New System of Cheniical Philosophy, p. 162. 
+ Vide Repulsion varying in a less ratio than attraction, and also the following 
law. 
