1867.] Physics. 555 



tlie vessels containing oxygen and hydrogen serve no other purpose 

 than that of keeping the water over which they stand fully satu- 

 rated with gas. The author has found that the electro-motive 

 force of the gas hattery is not modified by replacing the oxygen 

 vessel by one containing carbonic acid, and the general conclusion at 

 which he arrives is that the electro-motive force put into play in 

 Grove's battery is due exclusively, or almost so, to the affinity ex- 

 erted between the oxygen of the water and the hydrogen condensed 

 by the platinum electrode. 



A new force will have to be introduced into chemical physics — 

 that of capillarity. We notice it under the present heading, 

 inasmuch as the effects appear to be more nearly allied to those of 

 electricity than to any other force. M. Becquerel, sen., has been 

 experimenting for some time on what he now terms capillary 

 chemistry. He finds that chemical decompositions take place under 

 the influence of capillarity, and he thinks he has proved that these 

 curious phenomena are produced under the triple influence of 

 affinity, capillarity, and electricity. To demonstrate the interven- 

 tion of electricity, M. Becquerel has made the following experiment : 

 he immerses a split bell-glass, containing nitrate of copper, in a 

 second glass, containing a solution of monosulphide of potassium ; 

 then he dips the two extremities of a silver wire, one into the 

 nitrate and the other into the monosulphide. A constant electric 

 current is formed, and the deposit of silver is made, not in the 

 capillary slit, but on the iron. When the wire is removed, the 

 deposit is formed in the slit, and on the edges along the sides of the 

 split bell-glass. The capillary action is as powerful as an electrical 

 action. M. Becquerel has since improved his experiments ; for the 

 split bell-glass he substitutes prisms of crystal pierced with a small 

 hole ; the slit or fissure is replaced by plates of glass with edges 

 in contact, or even by sand, and he has thus obtained effects of 

 silvering, gilding, platinizing, and very remarkable deposits of gold, 

 silver, nickel, and cobalt. At one of the meetings of the French 

 Academy he exhibited several specimens of metals reduced and 

 precipitated by capillary action. In order to answer the objection 

 that these phenomena of reduction or precipitation might be attri- 

 buted to the action of the alkalies of the split glass tube, he has 

 employed polished plates of rock-crystal pressed one against the 

 other, so as to leave only a very small interval; he has thus 

 obtained perfect reduction of several metals. The interval between 

 the plates must be varied according to the different metals. For 

 the reduction of gold, for example, the space between the plates 

 must be less than that for copper. 



In an investigation on the inductive current of the Kuhmkorff 

 coil, M. Blaserna, Professor of the University of Palermo, has 

 arrived at the following conclusions respecting the passage of 



