and Observations on Lac . 
213 
When the properties of this substance are compared with 
those of bees-wax, a difference will be perceived ; and, on the 
contrary, the most striking analogy is evident, between the wax 
of lac and the myrtle wax which is obtained from the Myrica 
cerifera. 
An account of the latter substance has been published by Dr. 
Bostock, of Liverpool, in Nicholson's Journal, with compara- 
tive Experiments and Observations on Bees-Wax, Spermaceti, 
Adipocire, and the crystalline Matter of biliary Calculi.* . 
The properties of the myrtle wax, as described in Dr. Bostock's 
valuable Paper, so perfectly coincide with those which I have 
observed in the wax of lac, that I cannot but consider them as 
almost the same substance ; indeed I think they may be regarded 
as absolutely identical, if some allowance be made for the slight 
modifications which have been produced by the different mode 
of their formation. 
From the preceding experiments and analyses we find, that 
the varieties of lac consist of the four substances which have 
been described, namely, extractive colouring matter, resin, 
gluten, and a peculiar kind of wax. Resin is the predominant 
substance ; but this, as well as the other ingredients, is liable, in 
a certain degree, to variation in respect to quantity. 
According to the analyses which have been described, one 
hundred parts of each variety of lac yielded as follows. 
* Nicholson’s Journal for March, 1803, p. 129. 
