36 PROFESSOR KELLAND, ON MOLECULAR EQUILIBRIUM. 



hence the equation gives 



2 4 (e- aR + «Re~ aR ) {X - x) 



B 3 



\M 4nrP 



~ 7 ■ 2 S " Sf-»-'««- , ' + -*«"'>} (>-*). 



whence it evidently follows that 



KB? " ^^j ~ ' 



and — =1. 



Co 2 



The last equation merely verifies the operation, since the value of a 

 which it gives, is no other than its assumed value in (Art. 9). 



The other equation gives M = — 



cB 



~ P 



PM 



but from the nature of c, it evidently varies as P\ call it therefore 

 aP 2 , where a is a quantity independent both of M and P; the result 

 is 



, 4tt 

 a = ^' 



B ~^P' 



or a is the same for all substances, whilst B varies as the attractive 

 energy of the particle of matter. 



15. This conclusion is of great importance, as it enables us to cal- 

 culate the effect of any individual particle independently of those by 

 which it is accompanied. In fact, whatever be the nature of the mass, 

 any individual particle will be surrounded by an atmosphere of caloric, 



g-aR 



the density of which varies as — p— , where B is the distance from its 



