458 Intelligence and Miscellaneous Articles. 



high), falls into the capsule without wetting it, and instantly passes 

 into the spheroidal state. 



The experiment is recommenced in the open air when it rains or 

 when hail is falling ; and the results are the same as in the Pan- 

 theon experiment. Can it be said that in these experiments the 

 water and the hail are sustained in the capsule by the vapour which 

 envelops them ? Certainly not ; they are repelled instantane- 

 ously by the repellent force to which the heat in the capsule gives 

 rise. 



Let us now operate with non-volatile bodies, which cannot be 

 distilled, but are decomposed by heat. 



The capsule is heated as before, and small fragments of wax, 

 tallow, stearic or margaric acid are then thrown into it, or else 

 some drops of oleic acid or a fixed oil ; and this is what takes place : — 

 As the molecular motions are not transmitted with very great velo- 

 city, the body experimented on remains suspended over the capsule 

 without vapour and without gas proceeding from its decomposition ; 

 afterwards the gases resulting from its decomposition are liberated, 

 not from its surface, but from its interior : they take fire, and the 

 spheroid vanishes. 



The body under experiment not being volatile, giving off no 

 vapour, and the gases arising from its decomposition not being yet 

 produced, evidently the body can only be sustained beyond the radius 

 of the physico-chemical activity of the capsule by the repulsion of 

 the latter. — Comptes Rendus de VAcademie des Sciences, May 3, 1880, 

 t. xc. pp. 1074-1075. 



ON A GENERAL THEOREM ADVANCED BY PROF. CLAUSIUS IN 

 REFERENCE TO ELECTRICAL INFLUENCE. BY G. J. LEGEBEKE. 



In vol. i. of Wiedemann's Annalen* Prof. Clausius communi- 

 cated a theorem on the connexion between the electrical charges of 

 an arbitrary number of conductors which act by influence on one 

 another. That author deems this theorem very general and new, 

 and also assumes it in Part II. of his Mechanische Warmeiheorie, 

 p. 33. I wish to point out that Clausius's is a special case of a 

 more general principle, which, again, can itself be regarded as an 

 extension of a well-known equation of Gauss's. 



Over each of the closed surfaces C v C 2 , &c, named generally C, 

 a layer of a certain agent is spread, and acts by attraction or repul- 

 sion according to the usual laws. The density of the agent in 

 points of 



O x , C 2 , &c, C, 

 is represented by 



h v h 2 , &c, h, 



and the potential of all these layers in the same points by 



V 1? V 2 , &C, V. 



Secondly, the layers upon C 19 C 2 , &c, C, are replaced by layers 

 * See Phil. Mag. [5] iv. pp. 454 et seqq. 



