CHLORINE. 37 



verted into basic sulphate, and repeated recrystallizations 

 were made. ■ The salt was white and spectroscopically pure. 

 The determination was made in Gibbs' laboratory. [SiUi- 

 man's Amer. Journ. (2,) 4-^, 1870, 356.) 



D. Mendelejeff: 138 (0 = 16). 



Mendelejefl' first suggested raising the atomic weight of 

 cerium from 92 to 138. His reasons were a specific heat 

 determination which he had made with very impure metal, 

 and the fact that the supposed sesquioxide had never been 

 shown to exist. He believes that the atomic weight will 

 be found somewhat below 138, because that is the atomic 

 weight of barium. {Liebifs AnnaL, suppl., 8, 1871, 186.) 



H. BuEHRiG : UO.64.8 (0 = 16). 



Determined from ten analyses of the hydrous oxalate per- 

 formed by combustion in a current of pure oxj-gen behind 

 copper oxide. The water was collected in tubes filled with 

 calcic chloride, and the carbonic acid in potash. Five ex- 

 periments in which the cerium oxide was not determined 

 gave a mean of 94.1304, on the supposition that cerous 

 oxide contains 1 atom of oxygen and that O = 15.96, with 

 an extreme difference of 0.0445. Five determinations in 

 which the cerium was determined as eerie oxide gave 

 94.2260, with an extreme dift'erence of 0.0431. Carbon was 

 taken at 11.97. The mean result is Ce = 94.1782 for the 

 above mentioned assumptions, [or 140.648 for O = 16, and 

 on the supposition that cerous oxide is a sesqui-corapound.] 

 The oxalate was prepared from basic nitrate purified by 

 Gibbs' method of oxidation with minium and nitric acid. 

 The salt was spectroscopically pure. (Mrlmarm's Journ. far 

 Prak. Chem., 120, 1873, 222.) 



CHLORINE. 



The density of chlorine gas and the specific heat of chlo- 

 rine compounds leave no doubt that the atomic weight of 

 this element is nearly 35.5. {Gmclin- Kraut, I. c.) 



Marcet, Berzelius, Wollaston : 35.28 (0 = 16). 



Marcet, by experimenting on the calcination of pure mar- 

 ble, and on the saturation of chlorhydric acid with lime, 



