[ 3'o ] 
Ind melted again with frelh borax, until it fhews 
the blue colour. 
SECT. LI. 
Nickel is very feldom to be had, and as its 
ores are feldom free from mixtures of other metals, 
it is very difficultly tried with the blowpipe. 
However, when this femi-metal is mixed with iron 
and cobalt, it is eafily freed from thefe heteroge- 
neous metals, and reduced to a pure nickel regulus 
by means of fcorification with borax, in the fame 
manner as is mentioned Se6l. 1. becaufe both the 
iron and cobalt fooner fcorify than the nickel. 
The regulus of nickel itfelf is of a green colour, 
when calcined : it requires a pretty ftrong fire be- 
fore it melts, and tinges the borax with a jacint 
colour, Mapganefe gives the fame colour to borax, 
but its other qualities are quite different, fo as not. 
to be confounded with the nickel. 
SECT. Lir. 
Thus I have briefly defcribed the ufe of the 
Blow-pipe, and the method of employing it in the 
ffudy of Mineralogy. Any gentleman who is a 
lover pf this fcience, will, by attending to the 
rules here laid down, be able in an eafy manner to 
amufe himfelf indifcovering the properties of thofe 
works of nature which the mineral kingdom fur- 
nlflies ns with. The hufbandman may by its help 
find out what forts of ftones, earths, ores, &c. 
there are on his eftate, and to what ceconomical 
ufes they may be employed. The Scientific Mi- 
neraliil may, by examining into the properties and 
^ffefts pf the mineral bodies, difcover the natural 
relation 
