Mr Faraday's Repli^ to Dr John Davy's Remarks. 39 



his opinion is contrary to the fact, that neither of these gases 

 affect an electrometer,'"' &c. &c. Having similar feeHngs, I 

 thought that I was doing Sir Humphry Davy far more justice 

 in considering his expressions as general, and not particular, ex- 

 cept where they were evidently intended to be precise, as in the 

 cases which I formerly quoted (483 — 484)*. 

 , ; Again, Dr Davy says, " What can be more clear than this ; 

 that my brother did not consider water as essential to the for- 

 mation of a voltaic combination ?'*' &c. If this be so clear, how 

 happens it that Mr Brande, in the last edition of his Manual, 

 vol. i. p. 97, says that " Sir Humphry Davy further remarks 

 that there are no fluids^ except such as contain water ^ which 

 are capable of being made the medium of connexion between 

 the metals of the voltaic apparatus f** and Mr Brande's observa^ 

 tion is, " This, however, appears to me to admit of doubt P'* 

 How happens it also that Dr Ure, in giving his eloquent account 

 of Sir Humphry Davy"*s discoveries^, uses the very same words 

 as those I have quoted from Mr Brande, adding, ' It is pro- 

 bable that the power of water to receive double polarities, and to 

 evolve oxygen and hydrogen, isnecessary to the constant opera- 

 tion of the connected battery ?" I ought, perhaps, rather to ask. 

 How could Sir Humphry Davy use such words, and mean what 

 Dr Davy wishes to be considered as his meaning ? Why, there 

 can be no doubt that if I had proved that water was the only sub* 

 stance that could 'perform these duties^ Dr Davy would have 

 claimed the discovery Jor his brother. 



As I cannot impute to Dr Davy the intention of doing injus* 

 ticcy the only conclusion I can con:e to is, — that the language of 

 Sir Humphry Davy is obscure even to his brother, who thinks 



• I may be allowed to quote in a note a passage from one of Mr Pri- 

 deaux's papers, of the date of March 1833; I was not aware of it when 

 I wrote in answer to Dr Davy. Mr Prideaux says, " Sir Humphry Davy's 

 theory assumes that ' chemical and electric attractions are produced by the 

 same cause ; acting in one case on particles, in the other on masses : and the 

 same property, under different modifications, is the cause of all the pheno- 

 mena exhibited by different voltaic combinations.' A view so comprehensive, 

 embracing every modification of chemical as well as electrical action, seems 

 to include the other two, and every one tiiat has been or can be attempted on the 

 subject. But what it gains in extent it wants in distinctness."— /xwmA and 

 Edin. Phil. Mag.., vol. ii. p. 215. 



•f- Chemical Dictionary, ar<. ELKCTHiciTt. ^ ..- .• 



