additional facts regai 



320 Scienitfic Intelligence. 



power of this substance for gaseous substances. — Ber. Berl. Chem. 

 Ges., viii, 1616, Jan. 1876. g. f. b. 



5. The New Meted Gallium.— In the session of the French 

 Academy on September 20, the Secretary opened a sealed note de- 

 posited by Lecoq de Boisbaudeak, the first paragraph of which 

 reads thus: — "Day before yesterday, on Friday the 27th of August, 

 1875, between three and four o'clock in the afternoon, I obtained 

 indications of the probable existence of a new^ simple body among 

 the products of the chemical examination of a blende coming from 

 the mine of Pierrefitte, valley of Argeles, Pyrenees." The evidence 

 relied on to prove this discovery, a part of which evidence was 

 given in the sealed note and another part in a note read at the 

 same meeting, is: (1) the oxide (or perhaps a basic salt) is precipi- 

 tated slowly by metallic zinc in a solution containing chlorides and 

 sulphates; (2) its salts are easily precipitated by barium carbonate 

 in the cold ; and (3) it gives a spectrum showing two violet lines 

 of wave lengths 417 and 404 respectively. In all its other chemi- 

 cal reactions, it closely resembles zinc; though in the precipitations 



metal thus indicated, Lecoq de Boisbaudran gave the 



Hum. In a more recent pape" '- -'- ^^^^=~-^i '^^- 



the new metal, wliich he has 1 

 zinc. From it he has prepared a salt which he believes to be gal- 

 lium-alum. It is soluble in cold water, but is decomposed on heat- 

 ing, unless acetie acid be present. It crystallizes in octahedrons 

 and cubes, presenting the appearance of common alum, especially 

 under the microscope ; the crystals do not polarize light. Placed 

 in a super-saturated solution of ammonio-aluminum alum, they act 

 as nuclei and begin to grow. Treated witli ammonia, a part only 

 of the oxide is thrown down. In ammoniacal solution, the metal is 

 precipitated by electrolysis on the negative electrode. In the first 

 trial 1-6 milligrams were deposited in 4-J hours; in the second, 3-4 

 milligrams was deposited in 5 hours 40 minutes. (This sample was 

 submitted to the Academy.) The metal adhered strongly to the 

 platinum on which it w-as deposited. When burnished Tts surhn'o 

 is brilliant, and has a color between silver and platinum. \Mth ;i 

 feeble current, the metal comes down frosted and crystalline. It 

 does not decompose water at ordinary temperatures, and tarni>lu'> 

 slowly in the open air. With JlCl, it evolves hydrogen. On the 

 evidence of the alum, he fixes the formula of the oxide as GaoOg, 

 and assigns the metal to the aluminum group. In a sul»sequent 

 note, the author gives the results of the more accurate measure- 

 ment of the wave-lengths of the two lines of the gallium spectrum, 



being the stronger.— C. i?., Ixxxi, 493 (Sept.) 1100, (De< 

 Ixxxii, 168, Jan. 1876. c 



6. Gonductihility of Gases.— M. A. Wikkelmann h 

 ured the conductibilit'y of gases for heat by an apparatus 

 of Stephan, except that a peculiar manometer and m 



