C *25 1 
'mercury Is to divide the tin; and that the fal am- 
moniac ferves only to prevent the fufion of the ful- 
phur. 
The following proportion will anfwer better than 
that of the London Difpenfatory ; for there will be 
a greater produce of Aurum mofaicum, though a 
lefs quantity of mercury and fal ammoniac be ufed. 
Tin § 12, fulphur J 7, fal ammoniac 5 3, and 
mercury J 3. 
This proportion yields § ^7i of Aurum mofai- 
cum, whereas that of the London Difpenfatory gives 
only 5 16. 
The foluble part of the fublimate of Aurum mo- 
faicum anfwers far better for dying than any folu- 
tion of tin ; a fmall quantity of it with cochineal will 
dye iilk, and efpecially cloth, of a fine fcarlet colour ; 
filk may be dyed of a fine crimfon' colour, by its 
means, with the addition of brazil wood, peach wood, 
or braziletto ; but with logwood, filk and cloth may 
be made of a great variety of fine purple polours,, 
which feem lafting. 
The property, which this fublimate has of making 
finer colours than any folution of tin, engaged me to 
make many trials, with other preparations of tin;, 
and I found, that when tin was united to the acid of 
fait, and diftilled or fublimed, it would produce finer 
colours than any folution or combination of tin, un- 
fublimed or undiftilled. 
I mufi: be excufed for the prefent, for not telling 
the reafon of this ; it may be difcovered by examin- 
ing well the products, which are obtained by making 
the liquor fumans of Libavius, in the common man- 
ner. 
May 
