428 



Magneto-electrical Decomposition of Water, 



disk, but of less brilliancy. On communicating this to Dr. 

 Faraday, he kindly suggested the trying the effect of a piece 

 of wetted paper placed between the forehead and the con- 

 ductor : the result was, the figure was better defined and more 

 vivid. He further recommended the trial of a metallic disk, 

 point, and line, successively, instead of the hollow cylindrical 

 conductor as before; but no apparent change was visible in its 

 effects. The arrangements of the terminating wires of the 

 conductors is the same as already described in my former paper, 

 p. 169. Care must be taken that the wires of the conductors 

 are not removed from the mercury in which they are im- 

 mersed, otherwise (as I have experienced) a violent secondary 

 shock will be felt. 



The apparatus heretofore used for the decomposition of 

 water being defective, in so far that the connexions were im- 

 perfectly formed, did not thoroughly answer the purpose in- 

 tended for the magnetic electrical machine. I send you a 

 sketch of one constructed by myself, which answersy?///?/ the 

 purposes for which it was intended, and has given satisfaction 

 to all who have obtained them form me. 



Explanation of the Figure. 



A. A hard wood cup. 

 B B. Two copper wires, havitig two pla- 

 tinum wires, 

 C C, Soldered to their extremities. 



D. A piece of glass tube cemented 



into A. 



E. A cork fitting loosely into D. 



F F. Two glass tubes closed at one end 

 and fitted tightly into E. 

 Introduce B B into the connecting 

 holes of the magnetic electrical 

 machine, and move E F F from 

 D; pour dilute sulphuric acid 

 into D, so as to cover C C ; fill 

 the tubes F F also, and place 

 them as before. 



39, Charles street, Parliament street, 

 Feb. 14, 1835. 



Edwaiid M. Clarke. 



