THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



NOVEMBER 1842. 



I 



LV. Letter addressed by M. Edmond Becquerel to the Editors 

 of the Annales de Chimie et de Physique, in Reply to Mr. 

 Daniell's Letter to Mr. R. Phillips on the Constant Voltaic 

 Battery, inserted in the Phil. Mag. for April 1842*. 

 N the Annates de Chimie et de Physique for December 184-1 , 

 I published a Notice on constant voltaic batteries, in 

 which I stated the facts relating to the subject just as they 

 result from experiments performed by various natural philo- 

 sophers who have been occupied with this subject. 



Mr. Daniel], thinking that I had not done him justice, has 

 thought it necessary to reply to several of my assertions in 

 the Philosophical Magazine for April 1842. It was far from 

 my intention to have wished to say anything which might be 

 displeasing to him, and to have sought to misrepresent facts, 

 with a view to attribute to my father a discovery which did 

 not belong to him ; in this respect Mr. Daniell is strangely 

 mistaken as to my intentions, and without this motive, I should 

 not have replied to him, having nothing to change, with re- 

 spect to the main point, in the facts which I mentioned in my 

 notice. 



In every physical question three things are to be considered ; 

 the idea, the principle, and the applications. Now, it is proved 

 by undoubted facts, that from 1829, and even several years 

 before, my father had invented and constructed constant vol- 

 taic batteries, which, in truth, had not the power of action 

 and the advantages possessed by the constant voltaic batteries 

 of Mr. Daniel], who made them known in 1836. The ap- 

 paratus invented by my father at once received the denomina- 



* From the Ann. de Chim. et de Phys. for August 1842 (Third Series, 

 vol. v. p. 412), published towards the end of September. 



Phil. Mag. S. 3. Vol. 21. No. 139. Nov. 1842. Z 



