Chemistry and Physics. 217 



pper of the 



187V. 



1. Evolution of Hydrogen at both Electrode* in Ek-rtroh'/sis.— 

 Elsaesser has made the curious observation that if a wire of 

 nn be made the anode in a deeomposition cell i ontainhi"- 

 iric aeid, a wire of platinum bein^ made 

 the eatlmde, hydro-en -as is evolved at both eloetrodes, tleni-h at 

 the anode onh half a* much -'as appears as at the cathodeTaud 

 that this ratio, though the total evolution ot -as varies with the 

 •tvngth, remains constant. The same result happens 

 . :. ii >.;, ih \ dilute solution 

 sium sulphate is used; onlv in thi> ease, ma-nesium hy- 

 drate is deposited at Loth electrode^ Diiva quantitative experi- 

 ments showed that the quantity of magnesium dissolved at the 

 anode corresponded exactly to the quantity <>f hvdro-en set free 

 there; the volume of hydrogen evolved at die cathodt 



that set free in a voltameter in the same circuit. The 

 nee believes that the positivitv of the ma -nesium is so 

 increased by the current that it combines not onlv with the 

 ••xyuvn s, t tVe, l (v this current, hut also with a- hlitional oxygen, 

 --H which was united to it, appeann- in the tree state. 

 Why, however, this hvdroiren - half of that 



evoived at the cathode, is a question not yet capable of explana- 

 tion.— Ber. Berl. Chem. Ges., ix, 1818, January, 18 77. g. f. b. 

 3. Melatiim of the M<>h<-„1 •,- ■, :,<• i- ,f < /,. i d substances to 

 r, — \ ! KOKNJ has examined a number 

 ot simple liquids and also a number of solutions, with a view to 

 measure their power of absorbing beat, in order to trace some con- 

 nection between this property and g;b.ts, The 

 were concentrated upon a slit half a millimeter wide, 

 ; _ tin liquid to be examined, 

 i lene an spectrum. A thermo- 

 opening one millimeter wide was moved millimeter 

 ilong this spectrum, the deflection of the needle 

 ■ 

 i li'tt. d is , al adat, d; tin 'itference between the re- 

 M " r u '" ( -i; the tank is full and empty being due clearly to the 

 absorption of the liquid within it. The author concludes: 1st, 

 jnat the molecular absorb a- power appears to be constant: (A) 

 lor the elementary bodies when dissolved in the same medium ; 

 ■• ■ 

 gous chemical constitution \nion- other physical results, he has 

 observed that when thi irce of heat of known 

 ■ raU-d. the ab-rbia- p.-wer of bodies submitted to 

 ratio.— 

 J 'f ^ '■/,. II. XX.i, ;) ( .e !: ,^er. -7m O.F.B. 



*• On the K \/,,„, ,,,-s : ,' I'.irri <,,■ .,r C ■}„ „ i„ L*<,„i,,o.i* 

 Hatnt*.— IIkumaxx, in I is f urth pap* r < n the theory of luminous 

 Am - Jorji. Sci.-Tiiiud Sekies Vol. XIII, No. 75.— March, 1877. 





