S14 Intelligence and Miscellaneous Articles, 



ANALYSIS OF KUPFERNICKEL. 



M. Ebelmen states that this mineral comes from Ayer, in the val- 

 ley of Annivier (H' Valais). It possesses the usual characters of 

 Kupfernickel. It forms compact masses which are perfectly homo- 

 geneous, but exhibit no ti'aces of crystals ; the ore is mixed with 

 laminar carbonate of lime, which is easily separated by dilute hy- 

 drochloric acid. Its density is 7*39. 



The analysis was effected by treating the purified mineral with 

 aqua regia. The sulphuric acid was precipitated by chloride of ba- 

 rium and the excess of barium by sulphuric acid. The arsenic acid 

 was converted into arsenious acid by means of ebullition with sul- 

 phurous acid, and the arsenious acid was precipitated by sulphuretted 

 hydrogen. The sulphuret of arsenic obtained was, after drying and 

 weighing, analysed by aqua regia to obtain the sulphur ; by heating 

 another portion in a current of hydrogen, a minute residue of anti- 

 mony was obtained. The liquor freed from sulphuret of arsenic was 

 concentrated along with nitric acid, and precipitated by excess of 

 ammonia; an abundant precipitate of peroxide of iron was formed, 

 which retained a little nickel, ns appeared from its colour. 



It was redissolved on the filter by hydrochloric acid, and the 

 liquor was then treated cold with carbonate of bary tes. The peroxide 

 of iron only was precipitated ; the carbonate of barytes, with which 

 it was mixed, was readily separated. The liquor containing the 

 nickel was treated with sulphuric acid, and after filtration it was 

 added to the ammoniacal solution of the rest of the nickel ; this was 

 precipitated by excess of potash, and after drying and calcining, it 

 was weighed, and its quantity indicated that of the metallic nickel. 



The ammoniacal liquor, afterwards treated with hydrosulphate of 

 ammonia, yielded a slight black precipitate, which, collected, calcined 

 and weighed, gave with borax the reaction of cobalt. 



The results of the various experiments showed that the ore con- 

 sisted of — 



Arsenic 54<'05 



Antimony 0*05 



Nickel 43-50 



Cobalt 0-32 



Iron 0'45 



Sulphur 2*18 



Gangue 0*20 



100-75 

 Annales des Mines, tome xi. p. 5Q. 



ON THE DEHYDRATION OF MONOHYDRATED SULPHURIC ACID. 



M. Barreswil observes that anhydrous sulphuric acid has been 

 hitherto prepared by distilling protosulphate of iron or dry bisul- 

 phate of soda. These two processes produce an anhydrous salt 

 and sulphuric acid. The author states that he is not aware that an 



