340 Mr. Faraday's Reply to Dr. John Davy's Remarks. ' 



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

 that my brother did not consider water as essential to the 

 formation 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 ;" and Mr. Brande's 

 observation is, " This, however, appears to me to admit of 

 doubt."? How happens it also that Dr. Ure, in giving his elo- 

 quent account of Sir Humphry Davy's discoveries*, uses the 

 very same words as those I have quoted from Mr. Brande, 

 adding, " It is probable that the power of water to receive 

 double polarities and to evolve oxygen and hydrogen is neces- 

 sary to the constant operation 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 consi- 

 dered as his meaning? Why, there can be no doubt that if 

 I had proved that water was the only substance that could per- 

 form these duties, Dr. Davy woidd have claimed the discovery 

 for his brother. 



As I cannot impute to Dr. Davy the intention of doing in- 

 justice, the only conclusion I can come to is that the language 

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

 thinks it perfectly clear ; so obscure, indeed, as to leave on 

 his mind the conviction of a meaning the very reverse of that 

 which it bears to Mr. Brande and Dr. Ure. Thus Dr. Davy 

 puts his seal to the truth of Dr. Turner's observation! by the 

 very act of denying it. 



What makes the matter still more remarkable is, that Dr. 

 Davy charges it upon me as a fault, that I, and / alone, have 

 said what he denies in words, but proves in fact ; whereas 

 / have not said it, and others have. 



If Sir Humphry Davy's meaning is thus obscure to his 

 brother, I have no right to expect that mine should have been 

 rightly taken ; and therefore it is that I suspect, as I said be- 



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

 theory assumes that ■ chemical and electrical 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 phaenomeria exhibited by different voltaic combinations.' A view so 

 comprehensive, embracing every modification of chemical as well as elec- 

 trical action, seems to include the other two, and every one that has been 

 or can be attempted on the subject. But what it gains in extent it wants 

 in distinctness." Lond. and Edinb. Phil. Mag., vol. ii. p. 215. 



* Chemical Dictionary, art. Electricity. 



f And to that of Mr. Prideaux's also. 



