Nickel 341 



parated by the hammer, or by melting it, as 

 it melts much eafier than cobalt ; when 

 cobalt is by means of nickel united to bif* 

 muth, the compound is called Speifs; fo alfo 

 is a compound of cobalt, nickel, bifmuth, 

 fulphur and arfenic* 



15. In general, cobaltic ores are known 

 by their property of affording fympathetic 

 ink when digefted in aqua regia, after the 

 bifmuth is precipitated by the addition of 

 water. 



CHAP. XIV. 



Nickel 



I, Nickel is a reddifh white femi-metal of 

 great hardnefs, fo that it can fcarce be filed, 

 and of an equable texture I its fpecific gra- 

 vity varies according to its purity from 7,421 

 to 9,000, the pureft being the heavieft ; when 

 very pure it is in fome degree malleable, and 

 always magnetic, and hence it is deemed to re- 

 tain iron. The fufibility of the common re- 

 gulus is nearly as that of copper : it calcines 

 more difficultly than cobalt; its calx is green, 

 and rifes in a tuberofe fungous form ; it is 

 difficultly foli^ble in the vitriolic or marine 

 acid, but eafily in the nitrous ; all thefe folu- 

 tions are green, and volatil alkali turns them 



Z 3 blue. 



