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LVIII. On the Conductibility of Liquids for Electricity. By 

 MM. Van Breda and Logeman. In a letter to Professor 

 Faraday. 



Royal Institution, 

 My dear Tyndall, Oct. 31, 1854. 



I SEND the enclosed letter from MM. Van !^^'eda and Loge- 

 man to you as an Editor of the Philosophical Magazine. 

 If you should judge it proper for insertion in that Journal, I 

 shall be very happy to see it there, but will beg you to accom- 

 pany it on my part with the observation that it is not so con- 

 clusive in proving the negative (a thing very difficult to do) as 

 to move me at present from the reserved condition of mind 

 which I have recently expressed in respect of this matter. 



Ever yours truly, 

 M. Faraday. 



To Professor Faraday. 

 Sir, 



The experiments on electro-dynamic induction in liquids which 

 you have published in a letter to M. de la Rive, have excited 

 our lively interest, not only because the phsenomenon appeared 

 to us to be of importance in itself, but especially because it 

 seemed likely to throw some light upon the manner in which 

 electricity is propagated in liquids. 



Do liquids conduct exclusively by electrolysis, or do they also 

 possess a proper conductibility, similar to that of metals ? An 

 experiment that we have made may perhaps assist in the solution 

 of this question. It is well known that the conductibility of 

 liquids increases with their temperature, whilst the opposite 

 effect takes place with the metals, a fact which is easily explained 

 if we suppose that liquids^in general oppose less resistance to 

 decomposition in proportion as their temperature is raised. If 

 this explanation be the true one, the next thing to be ascertained 

 is, whether a liquid will also exhibit this increase of conductibility 

 for a current so weak as to traverse it without producing any 

 apparent chemical decomposition. If this were the case, it would 

 appear probable that the decomposition nevertheless took place, 

 and that it was by its intervention that the current passed 

 through the liquid. We have endeavoured to solve this question 

 by the following experiment. We passed the current of a small 

 DanielFs element through a column of distilled water 24 centi- 

 metres in length, contained in a glass tube of about 15 milli- 

 metres in diameter ; the electrodes were of platinum wire. One of 

 these electrodes was connected with the zinc pole of the battery, the 

 other with one end of the helix of a galvanometer of which the 



