Chemical Science. 173 



nium be heated by an alcohol lariip, it will lose its water, and 

 become of a deep green, nearly black. Let it be weighed, and 

 then heated to redness, it will appear to inflame at the moment 

 vividly. The cold oxide is of a fine green, has lost nothing in 

 weight, but is insoluble in acids, or at least the loss in weight 

 is so small as not to surpass 0.0025, and is occasioned by a 

 little acid that adheres to it, notwithstanding its being precipi- 

 tated with excess of ammonia. The acid becomes evident to 

 the smell at the moment of ignition. This phenomenon is of a 

 similar nature with the ignition of majiy metallic antimoniates, 

 gadolinite, and the hydrate of zircon. — Berz.An. C/iim. xvii. 12. 



4. Carburet of Nickel. — Carburet of nickel, when obtained 

 by heating the oxide with resin and oil, is, according to Mr. 

 Ross, a substance very much resembling plumbago in its appear- 

 ance, but is more micaceous. When nickel, reduced as above, 

 and consequently containing carburet, was reheated to fusion, a 

 portion of the compound rose to the surface, having the ap- 

 pearance of micaceous iron. It is not acted on by nitric acid, 

 and may therefore be obtained by dissolving out the nickel by 

 that acid. — Annals of PhiL ii. p. 149. 



5. On the Alloys of Chrommm, Iron, and Steel. — M. Berthier 

 has lately been engaged on these compounds, and has given 

 much interesting information respecting them, in a paper pub- 

 lished in tlie Annales de Chimie, xvii. p. 55. Chromium has so 

 strong an affinity for iron, that the presence of the latter metal 

 very much facilitates the reduction of the former, and the com- 

 binations which result are, according to M. Berthier, more ana- 

 logous to sulphurets and phosphurets than to alloys. The 

 oxide of chrome also has so strong an affinity for the oxide of 

 iron, as frequently to prevent its reduction, an effect that is not 

 observed with any other substance. 



Oxide of chromium heated very intensely, in a crucible lined 

 with charcoal, was completely reduced, and gave a button that 

 had sufTered hasty fusion, was brittle, hard, grey in some 

 places, grey-black in others, perhaps containing carbon in com- 

 bination. 



Mixtures of oxide of iron and oxide of chromium, in various 

 proportions, were heated in crucibles lined with charcoal, and 

 reduced, giving perfect combinations of the two metals. These 

 alloys are generally hard, brittle, crystalline, of a whiter grey 

 than iron, and very bright, less fusible, much less magnetic, and 

 much less acted on by acids than iron, and these characters are 

 more marked in proportion as more chromium is present. An 

 alloy, resulting from an equal mixture of pcr-oxides of iron and 

 oxide of chromium, gave a rounded button, full of cavities, lined 

 with prismatic crystals, its fracture crystalline. Its colour 



