23S A SYSTEM OF 
Thefe falfe notions have, however, induced a 
new, author to defcribe the cobalt as a mixture of 
iron, copper, lead, bifmuth, 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, fuch experiments are ex- 
pedted 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 eflablifh manufactures for making 
cobait-glafs, or zaifre, in any part of the world, 
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 aifo to 
apply it to fome pretended evil fpirit, which is 
faid to dwell in the mines : But time will abolifh 
thefe fuperftitions, which have their origin frorn 
ignorance. 
SECT. CCLIV. 
7. Nickel, Niccolum. 
This is the lateft difcovered femi-metaL 
It v/as firlf defcribed by its difcoverer Mr. 
Cronftedt in the A 61 :s of the Royal Academy 
of Sciences at Stockholm, for the years 1751 
and 1754, where it is faid to have the follow- 
ing qualities : That 
1. It is of a white colour, which however in- 
clines fomewhat to red. 
2. Of a Iblid texture, and fhining in its 
fracfures. 
Its fpecific gravity to water is as 8,500 
i; logo, 
4. It 
