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XI. An Investigation on the Chemical Nature of IVax. 
By Benjamin Collins Brodie, Esq. 
Communicated hy Sir Benjamin C. Brodie, Bart., F.R.S., 8fc. 
Received March 30, — Read May 11, 1848. 
II. On the Chemical Nature of a Wax from China. 
The wax which is the subject of the following investigation^ is a substance which 
was imported into this country from China as an article of commerce. Its appearance 
closely resembles that of spermaceti. It is, like spermaceti, white and, in large 
masses, highly crystalline, but differs from it by being harder, more brittle, and of a 
more fibrous character of crystallization. The melting-point of the wax is about 
83° C. It is but very slightly soluble in either alcohol or ether, but dissolves with 
great facility in naphtha, out of which fluid it may be crystallized. This substance 
is generally spoken of as a vegetable wax : on looking however into such facts as I 
can gather which throw’ any light on its origin, it seems more than probable that, 
like bees’- wax, it is the secretion of an insect. Sir George Staunton, in his “ Em- 
bassy to China*,” gives an account of a wax of insect origin, w’hich there formed an 
article of trade, and in his work may be seen a drawing of the insect and of the tree 
on wdiich the insect lives. Other writers on China give a similar account. In the 
Comptes Rendus for 1840'|' is a paper by M. Stanislas Julien, who gives an account 
of this tree wax, and states it to be the work of an insect : where may be found also 
a great number of extracts from Chinese writers on agriculture, giving an account 
of the insect itself and of the trees suitable for its food ; one of these trees is the 
Rhus succedaneum. This same gentleman, M. Stanislas Julien, gave to M. Lewy, 
w'ho was engaged in an investigation on these wax substances, a specimen of the wax 
from this very plant, which is therefore in all probability this insect-wax. The melt- 
ing-point, the appearance and the analysis of this wax, as given by M. Lewy, agree 
so exactly with those of the wax which I have examined, that I cannot but believe 
them to be the same chemical substance, and that this wax also is of insect origin. 
The existence of any other wax-making insect, such as this Coccus ceriferus, be- 
sides the bee, is a point of considerable interest in relation to the question as to the 
origin of the wax in that insect, and the possibility of the chemical transformations 
by which it is produced. 
* Vol. i. p. 352, edition 1797. 
t Vol. X. p. 619. The title is “Nouveaux renseignements sur la cire d’arbre, et sur les insectes qui la 
produisent.” See also in the same volume, M. Vikey, Sur les insectes qui produisent la substance appelee 
par les Chinois, “ Cire d’arbre.” 
