t$6 A SYSTEM OF 



Thefe falfe notions have, however, induced a 

 new author to defcribe the cobalt as a mixture of 

 iron, copper, lead, biimuth, and arfenic ; but he 

 has not at the fame time publifhed any experiments 

 which might ferve to confirm his opinion ; amongft: 

 which, with great reafon, fnch experiments are ex- 

 pected as imitate nature in this compofition, which 

 is pretended to confift of fo many different things. 

 It might then have been calculated, if it would 

 be profitable to eftablifh manufactures for making 

 cobalt-glafs, or zaffre, in any part of the w T orld, 

 where the above-mentioned ingredients can be 

 had. 



The word Cobalt in Germany, and efpecially at 

 the mineral works in Saxony, is applied to the 

 damps, the arfenic, its vapours, and their effects 

 on man ^ which has induced the vulgar alfo to 

 apply it to fome pretended evil fpirit, which is 

 faid to dwell in the mines : But time will abolim 

 thefe fuperftitions, which have their origin from 

 ignoranc* 



.■ - <, 



SECT. CCLIV, 



Nickel, Niccolum. 



This is the latefl difcovered femi- metal. 

 It was firit defcribed by its difcoverer Mr. 

 Cronftedt in the Ads of the Royal Academy 

 of Sciences at Stockholm, for the years 1751 

 and 1754, w r here it is laid to have tlie follow- 

 ing qualities : That 



1. It is of a white colour, which however in- 

 clines fomewhat to red. 



2. Of a folid texture, and mining in its 

 fractures. 



3. Its fpecific gravity to water is as 8,500 

 »' : 10,00. 



4. It 



