336 Intelligence and Miscellaneous Articles. 



crack, come into contact, which does not take place when the glass 

 is too thick. The Note contains some details on the operation of 

 this mixed electrocapillary apparatus, with a constant current, 

 without the intervention of an oxidable metal as in the couples of 

 voltaic piles. — Comptes Rendus de VAcademie des Sciences, vol. lxxxii. 

 pp. 354-356. 



ON THE CHEMICAL ACTIONS PRODUCED BY THE DISCHARGES 

 FROM AN INDUCTION-APPARATUS. BY M. BECQUEREL. 



The memoir commences by recalling the experiments of Wollas- 

 ton on the decomposition of water by the electricity from the ordi- 

 nary electrical machine, as well as those made by Faraday for the 

 purpose of rendering sensible the decomposition of salts, when he 

 sought solely to make evident the presence of acids and bases by 

 aid of test-papers. 



With a Ruhmkorff induction-apparatus, which gives a much 

 more rapid succession of sparks than the ordinary electrical machine, 

 more marked effects are obtained. The arrangement I have adopted 

 to exhibit them is the following : — Taking a plate of gutta percha 

 on which was placed a small slip of platinum in communication 

 with the positive pole of the apparatus by means of a metallic stem, 

 I applied to this slip of platinum a strip of paper moistened with a 

 metallic solution (copper or silver), and then to the paper the point 

 of a platinum wire connected with the negative pole. It was not 

 long before the metal was seen depositing around the point in ad- 

 herent layers. On a slip of platinum being placed between the 

 paper and the point of this metal, it likewise became coated with a 

 thin layer of metal. Submitting to experiment successively various 

 solutions, the apparatus operating with only two chromic-acid 

 couples, and sometimes with four, I thus obtained the reduction of 

 copper, nickel, cobalt, iron, lead, bismuth, antimony, zinc, cadmium, 

 silver, gold, and platinum. 



I likewise applied myself to the formation of amalgams by aid 

 of the same apparatus, following the method which Davy employed, 

 with the pile, to obtain the amalgams of potassium, sodium, and 

 other metals. On a slip of platinum which was brought into 

 contact with the positive pole of the apparatus I placed a piece of 

 caustic potass slightly moistened, and introduced into a small cavity 

 in its surface a drop of mercury in contact with the point of a pla- 

 tinum wire or the negative pole of the induction-apparatus ; after 

 a few moments the globule changed into a pasty amalgam in which 

 I perceived some crystals of this compound. 



The copper-amalgam was obtained by operating with a mixture 

 of a solution of nitrate of copper and nitrate of mercury with which 

 the band of paper applied on the platinum slip was moistened ; in 

 the same way were produced the amalgams of aluminium, magne- 

 sium, and other metals. I conceive that the discharges of an in- 

 duction-apparatus, when proceeding from electricity of high tension 

 and taking place in rapid succession, are capable of producing pow- 

 erful chemical effects. — Comj>tes Rsndus cle VAcademie des Sciences, 

 vol. lxxxii. pp. 353, 354. 



