THERMODYNAMICS OF THE YOLTAIC CELL. Ye: 
No. 2.—“ON OUR KNOWLEDGE OF THE THERMO- 
DYNAMICS OF THE VOLTAIC CELL.” 
Report of the Committee, consisting of Professor Lyle, M.A., 
Mr. W. H. Steele, M.A., and Mr. E. F. J. Love, M.A., 
F.R.A.S8. (Secretary). 
INTRODUCTORY NOTE. 
Your secretary desires to report that, owing to the removal of 
Mr. W. H. Steele from Melbourne, the active work of the Com- 
mittee devolved on himself and Professor Lyle. The report which 
follows was therefore drawn up by your secretary ; it was after- 
wards discussed critically by Professor Lyle, for w vhose valuable 
criticism your secretary desires to record his sincere thanks. 
REPORT. 
1. Preliminary. 
The application of the laws of thermodynamics to the voltaic 
cell was first made, in an incomplete manner, by Lord Kelvin,* 
who showed that the e. m. f. of a Daniell’s cell could be deduced 
with fair accuracy from the results of thermochemical experiments 
and Faraday’s Laws of Electrolysis, by an application of the first 
law of thermodynamics alone. In the second of the memoirs 
referred to he shows, however, that this conclusion cannot be 
regarded as general, pointing out that the ‘whole chemical 
action” is not in general—and may possibly not be in any case—- 
electrically efficient, owing to generation of heat within the cell. 
The equation given by Lord Kelvin for the Daniell cell may be 
written— 
WS (S.6e): Ah toe ee CA) 
the notation of which is too well known to require explanation. 
In this form it was made the subject of investigation by many 
observers, notably Favre, Raoult, and Braun ; they soon found 
that it was far from general, and to Braunt belongs the credit of 
being the first to suggest the application of the second law of 
thermodynamics to explain the discrepancies. Almost immedi- 
ately afterwards Willard Gibbs published his two epoch-making 
memoirs{ on ‘The Equilibrium of Heterogeneous Substances,” in 
* On the Mechanical Theory of Electrolysis.” Phil. Mag. Dec., 1851. ‘‘ Applications of 
the Principle of Mechanical Effect to the Measurement of Electromotive Forces,” &c. 
Phil. Mag. Dec., 1851. 
+ Wied. Ann. V. , p- 182, 1878. 
t Both are contained in Trans, Conn, Acad., iii, 1878. 
