398 Scientific Intelligence. 



(999-88 fine by mint assay) in presence of an equivalent quantity 

 of pure potassium bromide, and water. After three recrystalliza- 

 tions the salt was considered pure. An unweighed quantity, 

 from 12 to 15 grams, was placed in a large porcelain crucible, 

 previously weighed against a precisely similar crucible, and then 

 heated for some hours at a temperature gradually increasing to 

 about 160° after which it was still more strongly heated over a 

 small Bunsen flame. The auric bromide is readily decomposed 

 and the mixture of gold and potassium bromide is then weighed 

 against the crucible used as a tare. Three ratios were made use 

 of for fixing the atomic weight. The first was that of the gold 

 to the potassium bromide, obtained by dissolving out the latter 

 from the above mixture and weighing the remaining gold. The 

 second ratio was that of the residual gold to the silver required 

 to precipitate the bromine in the whole of the potassium bromide. 

 And the third ratio was that of the residual gold to the silver 

 bromide itself thus produced. All possible precautions were 

 taken to secure accurate results. Eight determinations were 

 made by the first method, the atomic weight varying between 

 196-85 and 196-90. Nine determinations by the second method 

 gave values varying from 196-78 to 196-90. Eight estimations 

 by the third method gave 196-77 as a minimum and 196-91 as a 

 maximum value. But it is better to deduce the final results from 

 the aggregate weights of the gold, potassium bromide, silver and 

 silver bromide. The mean of the first series thus calculated is 

 196-876; of the second 196-837; and of the third 196-842. The 

 mean of these values is 196-852, with a probable error of 

 ±0-0082. This the authors consider to be the atomic weight of 

 gold. — J. Chem,. Soc, li, 565, June, 1887. G. f. b. 



7. On the Occurrence of Alkaloid-Wee liases in Paraffin Oil. 

 — Welleb has called attention to the occurrence of basic bodies 

 resembling the alkaloids in a yellow paraffin oil of sp. gr. 0-850 

 to 0*860, obtained as a bye-product in the Saxony paraffin works. 

 To obtain these bases 500 kilograms of this paraffin oil were 

 agitated with dilute sulphuric acid, the acid decanted, mixed with 

 soda solution and agitated with ether; the operation being several 

 times repeated. A dark brown oily residue was left after distill- 

 ing off the ether which gave on distillation in a current of steam 

 a colorless oil of 0'98 to 0-99 specific gravity and having an in- 

 tense disagreeable odor, mouldy when cold and recalling pyridine 

 when heated. This oil contained nitrogen but neither sulphur 

 nor oxygen, and distilled unchanged between 220° and 260°. 

 Ammonium oxalate precipitates its solution in hydrogen chloride, 

 the precipitate being white and crystalline. By saturating an 

 alcoholic solution of the bases with oxalic acid, the oxalate is ob- 

 tained first in fine needles which rapidly increase to large plates, 

 extending through the solution. After recrystallization, the crys- 

 tals are pearly in luster and have a fatty feel, and are soluble in 

 hot water. — Ber. Berl. Chem. Ges., xx, 2097, July, 1887. 



G. r. B. 



