aS soe | 
) 4 
/ 
drawn from Animal Subfiauces. 287 
to filk. The tint was not in the leaft. weakened by wafhing. 
GC. Welter faturated this liquor with lime; and having com 
centrated it, he added alcohol, which took up a matter of a 
gummy appearance. The alcohol, diluted with water, being 
evaporated, there remained a yellow fubftance mixed with 
folutions of the nitrat and muriat of lime. Thefe falts were 
decompofed by carbonat of pot-ath, and the liquor, feparated 
from the carbonat of lime, was fubjeéted to evaporation. It 
gave golden-coloured cryftals, which had the finenefs of filk; 
and detonated like sunpowder, producing a black fmoke. 
Thefe cryftals are foluble in water and alcohol, and cryftallife’ 
on cooling. They are deprived of their colour by the oxygen- 
ated muriatic acid. The fulphuric acid difengages from them 
the odour of the nitric acid. The muriatic acid precipitates, 
from a folution of them, {mall micaceous, whitifh, volatile cryf- 
tals, which in the fire exhale a bitter and inflammable fmoke. 
This golden-yellow coloured detonating and cryftallifablefub- 
ftance i3 by the author called amer (bitter) ; its cryftals appear 
to be oétaedral. As.animal fubftances become yellow by the 
contact of the nitric acid, C. Welter endeavoured to extra 
amer from raw beef; but he found it combined with another 
fubftance, which, like it, could not be altered by the nitric 
acid. This combination, foluble in the concentrated nitric 
acid, is feparated from it by water, under the form of a yellow 
powder, which does not lofe its colour by expofure to the air, 
and which might perhaps be ufeful in painting. 
What made, C. Welter prefume that this powder is com- 
pofed of amer and another fubitance, is, that he obtained the 
Jatter by treating fponge with the nitric acid. It is colour- 
lefs, foluble in concentrated nitric acid, and fuffers itfelf to 
be precipitated by water like the preceding powder. 
What has been here faid feems to fhew that animal mat- 
ters treated with the nitric acid give a3 refiduum two fub- 
ftances unalterable by that acid, and which are found either 
in the {tate of combination, or feparate. It appears that filk 
gives pure amer, {ponge gives the fecond fubftance pure, and 
beef a combination of both. The amer is yellow, and foluble 
in water: the combination of both is as infoluble in water 
as the fubftance obtained from fponge, but coloured. 
XV, Reflec- 
