Prof. Apjohn on the Specific Heats of the Gases. 339 



cess be expressive of the truth, we shall perceive, first, that 

 the susceptibility to induction in electrospheres will increase 

 with the number of electrical atoms in their external and im- 

 perfect strata, so long as the number is not too great for all 

 of them to be equidistant from the two contiguous central 

 nuclei ; and, secondly, as the limited number will be greater 

 as the electrospheres are more voluminous, that the in- 

 ductive susceptibility will be the more exalted as the electro- 

 spheres are larger. Now we have found reason to believe 

 that induction, as evidenced by compensation, increases with 

 the atomic weights of bodies (28.); and if this be true, the 

 conclusion to be deduced from the fact obviously is, that the 

 volumes of electrospheres vary as their weights, or in other 

 words, that the minor electrical force is the cause of gravita- 

 tion. 



85. The justness of such a conclusion will be made more 

 apparent in the next part of this treatise ; in which we shall 

 endeavour to show that the principles we have promulgated 

 are adequate to explain all the phaenomena of electrical ex- 

 citation. 



[To be continued] 



XL VI. The Spectre Heats of the Gases as deduced by Dr. 

 Apjohn, compared with the more recent Results qf Dr. 

 Suerman. By James Apjohn, M.D., M.R.I.A., Professor 

 of Chemistry in the Royal College of Surgeons, Ireland. 



[Continued from p. 273, and concluded.] 



A T the close of the paper which I have submitted to the 

 -^^ Royal Irish Academy, I have hazarded the following pro- 

 positions, which would seem to be justified by the results of 

 my researches. 



1. The simple law so much insisted upon in modern times 

 by Haycraft, Marcet, and De la Rive, and others, that equal 

 volumes of the different gases have the same specific heat, is 

 not the law of nature. 



2. The more limited conclusion announced by Dulong, 

 that the simple gases have under equal volumes the same spe- 

 cific heat, is probably not true in a single instance, and is al- 

 together at variance with my result for hydrogen. 



3. The numbers at which I have arrived correspond tole- 

 rably well with those of De la Roche and Berard except in 

 the case of hydrogen, to which I ascribe a specific heat greater 



Z2 



