characteristic than their respective chemi- 
cal composition or sensible properties. 
lave nowhere met with any account of the 
. effects of this gum-resin, apart from those 
of true Ceylon Gamboge with which it has 
been commonly confounded. But I have 
— made some trials with it, which prove that 
. itdoes not by any means possess the pow- 
erful cathartic action of Gamboge. One 
individual took first ten, and afterwards 
. fifteen grains, finely pulverized with bitar- 
- trate of potash, but without experiencing 
any effect whatever ; and another took eight 
. grains of the resin, or the equivalent of 
twelve grains of the crude substance, also 
without the slightest perceptible effect. 
. : These quantities are about thrice the aver- 
. age doses of true Gamboge. 
| On the whole, then, looking to the ex- 
. ternal characters, the chemical composition, 
i and the physiological operation of the gum- 
 Tesin of Garcinia cambogia, it seems very 
difficult to account, except on the suppo- 
sition of loose observation or hypothetical 
| inference, for the belief long generally en- 
tertained, and still not abandoned by some, ! 
that this tree yields either the Gamboge of 
. Commerce, or a substance analagous to it. 
Mr. Royle having expressed an opinion 
An his /lustrations of the Botany of the 
Himalayah, Mountains, that a kind of 
Gamboge may also be produced by another 
Species of the natural family Guttifere, 
2Ó n Xanthochymus pictorius,® it 
o me desirable to determine that 
point also by an analysis of its resinous 
Ee Mrs. Walker's specimens 
The T ^ my power to accomp ish. 
Va udation on the bark of this spe- 
ud hee more different in appearance 
2l EU amboge than that of the Gar- 
mbogia. [t forms small tears of a 
pale Srayish-green colour, 
n Poreh-green; and it is translucent 
| in. It does not form an emulsion 
at all when rubbed with 
is pretty hard with the wet finger. It 
e mid , and in pold weather pulver- 
- 
eee 
= 
E 
T. 
Lc I ctp uie. t IEEE a y RSEN "BE 
E e 
* 
* Sucha CN 
on my iu his Phytographie Médicale, ii, 
3 
* Paris, i821, 
Mlastrations, &c. p. 132. Part iv.—1834. 
ON THE SOURCES AND COMPOSITION OF GAMBOGE. 
245 
From the facility with which it softens 
when heated, it probably contains some 
volatile oil; but my specimen could not 
afford me enough for ascertaining that point 
with care. For the same reason I could 
not attempt an exact quantitative analysis 
of its other component parts. But it is 
evidently a true gum-resin—containing, 
however, less gum than that of the Hebra- 
dendron. Sulphuric ether removes a pale 
greenish-yellow resin, leaving an opaque 
glutinous mass, which is broken up and 
partially dissolved by cold water. The 
watery solution froths on agitation, and 
when evaporated leaves a viscous matter, 
evidently Arabin, or soluble gum. A sm 
quantity of fibrous impurities and fleecy 
particles remains unattached by the ether 
and cold water. One grain and seven- 
tenths of the gum-resin yielded 1.3 of re- 
sin, 0.3 of gum, and 0.2 of fibre, that 1s, 
76.5, 17.6, and 5.9 per cent. This result 
seems to indicate the absence of volatile 
oil; but it cannot be relied on absolutely, 
on account of the small scale of the ana- 
lysis. The result, however, is sufficiently 
accurate to show, when taken along with 
the sensible qualities of the gum-resin, 
that the Xanthochymus pictortus does not 
yield an exudation resembling in any ma- 
terial property the true Gamboge of the 
Hebradendron. 
There still remains a fourth Guttiferous 
plant, which has been supposed to yield a 
concrete juice similar to Gamboge, namely, 
the Garcinia pictoria. This I have not 
hitherto been able to obtain. Dr. Rox- 
burgh mentions in his Flora Indica, that 
it seemed of a finer colour in its crude 
state than any other kind, but that the tint 
was not permanent? I can scarcely anti- 
cipate any other conclusion, from a careful 
examination of its properties and compo- 
sition, than that, like the two substances 
described above, it possesses: the generic 
characters of a gum-resin, but is otherwise 
only remotely analogous to the true Gam- 
boge of Ceylon and Siam. 
3 Flora Indica, ii. 629- 
— 
