[ ’'26 ] 
May not Iron and copper, united to the acid of 
fait and fublimed, anfwer better for dying, than 
other preparations of iron and copper ? 
Moll other metallick fubftances may be after this 
manner more intimately combined with a greater 
portion of fulphur than by fulion. Bilmuth is the 
only one, which produced a golden colour, and that 
not fo fine a one as Aurum mofaicuin. Iron, cop- 
per, lead, and regulus of antimony, produce black 
combinations ; arfenic forms a reddidi mafs like real- 
gar j zinc does not in this manner, nor in any other 
way that I know, combine with fulphur. 
Ah Apparatus for ?naking Aurum Mojaicim in the 
cheapejl manner^ 
A glafs vefTel cannot be ufed for this operation 
more than once, becaufe it is neceffary to break it, to 
get out the Aurum mofaicum. The following 
utenfil may be employed a great number of times, 
and fave the expence of glafs. 
Take a black lead crucible, N°. 6o ; bore a round 
hole in its bottom about three inches diameter ; and 
faw off an inch of its upper edge ; if it has a lip, 
get a round piece of burnt clay, of an inch thick 
or rather more, to fit exadly into this edge; the 
compofition, which is ufed for making paving-tiles, 
anfwers very well for this purpofe. In order to 
make ufe of this apparatus, fit the round piece of 
burnt clay to the inner edge of the crucible, by 
means of fome loam foftened with glue, and dry it 
flowly ; then turn it upfide down, and lay it in a 
proper furnace on two iron bars. The mixture for 
the Aurum mofaicum is to be put in through the 
round 
