Correspondence. 



107 



In conclusion we would again remark, that the essential 

 requisite for a thorough comprehension of Faraday's theory 

 of electro-chemical decomposition is a clear conception of 

 the electric current as " an axis of power having equal and 

 contrary forces." This conception being once distinctly and 

 vividly impressed upon the mind, no difficulty will be expe- 

 rienced in undertaking all the varied phenomena of decom- 

 position, and the efforts made in mastering the key, will be 

 more than rewarded by the new view, its possession will af- 

 ford access to.* 



Camp, Sd February, 1843. 



From J. G. Malcolmson, Esq., F. R. S. to the Editor of the 

 Calcutta Journal of Natural History/, Bombay, Nov. 10, 1842. 

 My dear Sir,— I have just received your 10th Number, and 

 think that a remark of Captain Campbell, relative to myself, accom- 

 panying some extracts from Dr. Boase's letters, requires, a short an- 

 swer. But although the occasion is unpleasant, my object is merely 

 to solicit Captain Campbell to place less confidence in authority, 

 and to employ his talents and his great opportunities in a course of 

 careful research by which the science to which he is devoted may be 

 advanced, instead of attempting, by somewhat hasty observations, to 

 rebuild forgotten hypotheses, or to invent a science from the founda- 

 tion, like the palace of air presented to Thor, by the giant Skrimis 

 in Jholhim land, " things that dreams are made of," 



It is evidently Captain Campbell's duty to learn what has been 

 done ; what has been proved by evidence which none can dispute, 

 before he writes and acts as if the opinions received by all good 

 geologists, were of the class of crude speculations long current 

 in Saxony and Edinburgh ; things that any man may invent at his 

 pleasure. 



* Our readers will regret the close of this series of papers on the 

 analysis of Faraday's Researches in Electricity, which evince so close 

 and philosophical an examination of the subject by Lieut. Smith. — Eds. 



