400 Intelligence and Miscellaneous Articles. 



philosophical views and intuitive results. In the second part, par- 

 ticularly, M. Him points out how one might, in his opinion, render 

 the laws of Mariotte and Gay-Lussac applicable to all bodies, on 

 condition of adjoining to the pressure jp, which enters into them, a 

 fictitious pressure E equivalent to what he calls the sum of all the 

 molecular actions, which would not be dependent on the volume. 

 He thus arrives at the formula 



v 

 (■p + E) - = K = constant, 



coinciding with the la\vs of Mariotte and Gay-Lussac for E=0. 



It will be seen that this formula and our (A) would be identical 

 if it were admitted that, for all bodies, the function V, introduced 

 by our analysis, follows a simple law of proportionality. It is very 

 remarkable that analysis thus confirms, not in whole, but at least 

 in part, the results to which M. Hirn was led by the profound me- 

 ditations developed by him in what he calls the second part of ther- 

 modynamics, the part which might be named philosophic and spe- 

 culative. Our law (A), provided the fundamental hypothesis of 

 molecular mechanics be admitted, must evidently be ranged in the 

 first, the rigorous part. — Comptes Rendus de VAcademie des Sciences, 

 Sept. 23, 1878, tome lxxxvii. pp. 449-452. 



ON DIFFUSION AS A MEANS FOR CONVERTING NORMAL-TEMPE- 

 RATURE HEAT INTO WORK. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 

 In the Philosophical Magazine for September last is a translation 

 of a paper* by Professor Clausius, replying to an article of mine on 

 the subject of the work to be derived at the expense of normal-tem- 

 perature heat through diffusion - }". After expressing his agreement 

 with the general principle involved, Professor Clausius states, "only 

 on one point I think I must express a view different from his." 

 "Will you allow me to express my thanks to Professor Clausius for 

 his kindly criticism, and, in justice to myself, to point out that I 

 had already seen my mistake and retracted itj. 



I am, Gentlemen, 



Tours faithfully 

 London, October 1878. S. Tolvee Peeston. 



* Wiedemann's Annalen, July 1878, p. 341. 



t ' Nature/ Nov. 8, 1877, p. 31 ; and Jan. 10, 1878, p. 202. 



% 'Nature,' May 23, 1878, p. 92. 



