334- Prof. Grove's Remarks on a Letter of Prof. Daniell. 



of these philosophers ; I cannot see that I have. I have on 

 many occasions mentioned their experiments before my own 

 in the history of the voltaic pile, both as acknowledging their 

 priority and as not wishing to claim what was not my due ; 

 probably it is this which has led to a misconception on the 

 part of Mr. Daniell, but I have distinctly stated the idea 

 which immediately led to the construction of my battery in the 

 paper which describes it (Phil. Mag., May 1839). After de- 

 tailing an experiment with two strips of gold-leaf in nitric and 

 hydrochloric acids separated by a porous diaphragm, and 

 showing that upon contact of the two strips the gold in the 

 hydrochloric acid was dissolved, and that a voltaic current 

 was established, I say, " It now occurred to me, that as gold, 

 platina and two acids gave so powerful an electric current," a 

 fortiori " the same arrangement, with the substitution of zinc 

 for gold, must form a combination more energetic than any 

 yet known :" this was the simple deduction which led to my 

 subsequent experiments. I have in most cases been content 

 to publish experiments with no more of theory than was re- 

 quisite to connect them ; it is a general and I think a just com- 

 plaint that there are already too many speculations on this sub- 

 ject ; but in a letter published in the Philosophical Magazine 

 for Feb. 1839, p. 129, previous to the discovery of my battery, 

 I gave my own notions of the principles of voltaic batteries, 

 notions which in some respects agree with those of Mr. 

 Daniell, but which also suggest some new views of voltaic ac* 

 tion. There is one experiment there detailed in which copper 

 is reduced by copper, which had much influence on my subse- 

 quent experiments, but which is not explicable by any prin- 

 ciples laid down by Mr. Daniell; at the conclusion of this 

 paper I say, " if these principles be correct, very superior 

 combinations may be discovered:" how this prediction has 

 been fulfilled the public is the best judged 



Far be it from me to disclaim any assistance from the ex- 

 periments of Mr. Daniell or of M. Becquerel; I shall ever re- 

 tain a grateful recollection of the assistance rendered to my 

 first efforts in science by the latter gentleman. I cannot at this 

 distance of time well describe what effect their experiments 

 had upon my mind. In the progress of science it is difficult 

 to define the frequently unperceived effect of prior discoveries 

 upon subsequent experimentalists, but I cannot for many rea- 

 sons acquiesce in the assertion of Mr. Daniell above quoted. 



Mr. Daniell was for a long time attached to the theory of 

 the deposition of metals in the voltaic circuit being the result 

 of a secondary action of the nascent hydrogen, a theory ge- 

 nerally adopted until combated by Hisinger and Berzelius ; thus 



