On pure Nickel. j4I 



nities of making this observation in the course of my es- 

 pennieuts. Some nickel, Irom which I had separated the 

 iron* and the arsenic in the humid way, and which 1 liad 

 afterwards reduced with the addition of a combustible 

 substance, was malleabJe, and attracted the niaoiiet 

 though not so foicibl)' as pure nickel. The same tnetaC 

 purified with less care, was less malleable, and proportiouallv 

 less attractable by the magnet. Kepeated exposure of the me- 

 tal to theaiost powerful heat of a porcelain furnace did not 

 m the least restore to it this propertv.— Some experiments 

 which I shall hereafter relate, have convinced me, that 

 copper cannot be entirely separated from nickel in the 

 humid way, and that the only means of separating them is 

 to reduce the cupreous oxide of nickel by lire. 



The sulphuric and muriatic acids exercise but little action 

 on nickel. Even its oxide by air does not dissolve in the 

 latter without the assistance of a strong eballision. The 

 most appropriate solvents of nickel are the nitric and nitro- 

 munatic acids. I have already mentioned, that impure 

 nickel, particularly the cupreous, is attacked by the nitric 

 acid with hcgt and vivacity. 'Hie action of the same acid 

 on pure nickel is a little different, and particularly on tht 

 hammered metal. I have poured nitric acid on nickel both 

 m buttons and laminated, expecting a very active solution j 

 but it has proceeded slowly, and I have even been oblujed tJ 

 have recourse to the heat of a spirit lamp to accelerate it. 

 The dissi:^tion, however, having appeared to cease, I de- 

 canted the liquid and poured on the residuum a fresh quan- 

 tity of acid of the same strength as the precedino-,, wheu 

 on a sudden such a brisk action came on, accompanied 

 with the evolution of heatf, that I could not remove the 

 capsule to the fire-place quickly enough. 



I shall now proceed to consider sonfe of the characters of 

 pure ruckel in the state of oxidation. 



The nitric solution of pure nickel has a beautiful oiass- 

 green colour. Carbonate of potash separates from it a pale 

 apple-green precipitate. This precipitate well washed and 

 dried IS very light. A thousand parts of metallic nickel re- 

 duced to this precipitate weigh -2-g27 parts. 



• The separation of the iron succeeds best bv a r.apid evaporation of the 

 n.tnc iolut.on of tJ.e ferruginous nickel, by wLich the iroJ/is precipitated 

 m the form ot an msolubk- oxide. At the . anc time a little at.onic 

 IS separa.ed in unioa with ihe iron. It is pref<u^ablei however, to senar.ite 

 tJiearscmc first, wh,ch is effected by the help of a nitric solution of lead 

 Ihe lead isafierward* to be precipitated by a .olution of sulphate of potash" 



+ From this it u ditRcult to heUave that nickel, under favourable circum* 

 %TM7nT '^' "" "'"'^"^ t^y'^ecornbined influence of air and fire.— 



If 



