210 Mr. Hatchett’s analytical Experiments 
g. Acetic acid dissolves it with great ease, and forms a deep 
brownish-red solution. 
10. Acetous acid does not dissolve it quite so readily, but the 
solution is of a brighter red. Both of the above, when saturated 
with alkalis, are changed to a deep reddish-purple. 
11. The lixivia of potash, soda, and ammonia, act powerfully 
on this substance, and almost immediately form perfect solu- 
tions, of a beautiful deep purple colour. 
12. Pure alumina, put into the aqueous solution, does not 
immediately produce any effect; but, upon the addition of a 
few drops of muriatic acid, the colouring matter speedily com- 
bines with the alumina, and a beautiful lake is formed. 
13. Muriate of tin produces a fine crimson precipitate, when 
added to the aqueous solution. 
14. A similar coloured precipitate is also formed, by the addi- 
tion of solution of isinglass. 
These properties of the colouring substance of lac, especially 
its'partial solubility in water and in alcohol, and its insolubility in 
ether, together with the precipitates formed by alumina and 
muriate of tin, indicate that this substance is vegetable extract, 
perhaps slightly animalized by the coccus. 
The effects which it produced on gelatin, also demonstrate 
the presence of tannin ; but this very probably was afforded by 
the small portions of vegetable bodies, from which the stick lac 
can seldom be completely separated. 
Properties of the Resin of Lac. 
This substance is of a brownish-yellow colour; and, when 
put on a red-hot iron, it emits much smoke, with a peculiar 
sweet odour, and leaves a spongy coal. 
