as to the Constitution of Chlorine. 



37 



by the spectroscope I must refer to the above papers ; my pre- 

 sent purpose is to point out an interesting fact connected with 

 its application to chlorine and its compounds. 



The maximum number of degrees of freedom which a mo- 

 lecule composed of n smooth rigid spheres could possess would 

 be Sn ; but the forces in play between the spheres might, as 

 in the case of air and the other gases above referred to, reduce 

 the number to much below this amount. Thus the value of 

 m + e could not exceed, but might be less than 3n + e. For 

 gases in which the molecule consists of two atoms, e — ; but 

 in the cases of more complex combinations we can say only 

 that, caiter is paribus, we should expect that its value would 

 increase with the number of atoms in the molecule. Bearing 

 these facts in mind, the following Tables lead to a curious 

 result. In the first column of each are placed the symbols of 

 the substances referred to. In the second columns are the 

 ratios of the specific heats, deduced (except in the case of mer- 

 cury) from Regnault's experiments by the use of equation (1). 

 In the third are the values of m 4- e (omitting fractions) de- 

 duced by equation (2). In the fourth are the values of 3n, 

 where n is the number of atoms of which the molecule is com- 

 posed. 



Table I. 



I. 



II. 



III. 



IV. 







m-\-e. 



3n. 



Hff 



1-666 

 1413 

 1-403 

 1-409 

 1-417 

 1-403 

 1-416 

 1-243 

 1-302 

 1-335 

 1-265 

 1-276 

 1-198 

 1-300 

 1-290 

 1-144 

 1-110 

 1-059 

 1-059 

 1-283 

 1-060 

 1-091 

 1-072 

 1-031 



3 



5 



5 



5 



5 



5 



5 



8 



7 



6 



8 



7 



10 



7 



7 



14 



18 



34 



34 



7 



33 

 22 

 28 

 64 



3 



6 



6 



6 



6 



6 



6 



9 



9 



9 



9 



9 



9 



12 



15 



18 



27 



45 



45 



27 



42 



30 



36 



78 



Air 



o 



N 2 



H 9 



NO 



CO 



N 



H 9 



H 2 S 



C0 



so 2 



cs 9 



NH 3 



OH A 





C 2 H 6 



C 4 H ]0 O 



°4H 10 S 



o 8 b: 6 n 



C 4 H 8 2 



C 3 H 6 



C io H 16 



