18 ATOMIC WEIGHT DETERMINATIONS. 



J. Weeren : 13.83 (0 = IG) ; 8646 (0 = 100). 



Weercn followed the same method as Awdejew, except 

 that he precipitated the beryllium with ammonium sulphide, 

 the oxide being soluble in excess of ammonia. The mean 

 of four experiments gave 57.64, the extreme difference 

 being 1.52 for O = 100, [57.64 is f of 86.46.] Weeren 

 took^S = 200. {Poggeml. Annal, 92, 1854, 124.) 



G. Klatzo : 13.89 (O = 16). 



Klatzo made five analyses of the sulphates containing 

 seven and four molecules of water, precipitating the sul- 

 phuric acid as barium sulphate, and the beryllium as oxide 

 by means of ammonia. From a comparison of the sum of 

 the oxide found in all the analyses with the total amount of 

 barium sulphate found, Klatzo deduces Be = 9.227, for Ba = 

 137, and S = 32. [If Ba is taken equal to 137.16, and S = 

 32.07, and if each of the analyses is calculated for itself, Be 

 = 13.89. The extreme difference is 0.45.] The sulphates 

 were purified by recrystallization, and treatment wnth alco- 

 hol. {Erdiiianii's Journ. far Prak. Cheniie, 106, 1868, 227; 

 Klatzo, Ueber die Constitution der Beryllerde, Dorpat, 1868.) 



L. F. Nilson and 0. Pettersson have redetermined the 

 specific heat of beryllium within a few weeks. They find 

 the specific heat 0.4079, corresponding to a trivalent metal 

 and a sesqui-oxide. The investigation seems to have been 

 made with great care, while that of Emerson-Reynolds was 

 merely preliminary. (Berlin, Bericht der chcm. Ge.s., 11, 1878, 

 386.) 



BIS:\IUTH. 



Dulong and Petit, Regnault, and Kopp, have determined 

 the specific heat of Bismuth. It corresponds to an atomic 

 weight of about 210. {Gmelin-Kraut, I. c.) 



P. Lagerhjelm : 212.86 (O = 16) ; 1330.377 (0 = 

 100). 



Metallic Bismuth was oxidized in a weighed vessel by 

 nitric acid, and the nitric acid expelled by heat. 10 grammes 

 of bismuth gave 11.1275 oxide. {Berzelius' Lehrbuch der 

 Chemie, 5th ed., 3, 1216; Stockholm, Akad. Handl, 31^, 1313, 

 219.) 



