and Observations on Lac . 
*99 
a deep yellow opaque brittle substance, which, by a sufficiency 
of nitric acid, and continuation of the digestion during about 48 
hours, is dissolved. 
The solution however is turbid, and, when poured into a 
large quantity of distilled water, deposits some yellowish flocculi, 
which, being collected, are found to be a sort of wax. 
The filtrated liquor is of a bright golden yellow ; and, when 
saturated by ammonia, changes to orange colour, but does not 
yield any precipitate, nor any traces of oxalic or malic acid. 
This yellow nitric solution is converted, by evaporation, into 
a deep yellow substance, which burns like resin, but is soluble 
in boiling water. 
The alkalis and lime, being added to this aqueous solution, 
do not produce any precipitate, but the yellow colour is very 
considerably deepened ; and, by evaporation, an orange-coloured 
substance is obtained, which is still easily soluble in water, and 
consists of the deep yellow substance abovementioned, com- 
bined with the alkali or lime. 
6 . Muriatic acid dissolves the colouring matter and gluten 
of lac ; but its action on these is feeble, unless the resin has been 
previously separated. 
7. Acetous acid, in its effects, much resembles muriatic 
acid. 
8. Stick lac, seed lac, and shell lac, are partially dissolved by 
acetic acid ; and, if this be heated, a considerable portion is 
taken up. 
The dissolved part consists of the colouring extract, of resin, 
and of gluten ; the wax being the only ingredient which is in- 
soluble in this menstruum ; but a portion of the former substances, 
mdccciv, D d 
