ILLUSTRATIONS OF INDIAN BOTANY. 119 
Tam here again indebted to Mrs. Colonel Walker for my subjects of analysis, having very 
lately received splendid specimens of the barks of both trees, with their exudations concreted 
on them. 
The exudation of Garcinia cambogia, as 1 am informed by Mrs. Walker, concretes slowly 
and imperfectly, so as to remain long viscid in the climate of Ceylon. ‘Tho specimens sent to 
me, on arriving here, still continued soft enough to receive the impression of the fingers when 
squeezed between them. The exudation was chiefly in the form of long slender tears, of a 
_ Suspecting that its softness was owing to the presence of volatile oil, T distilled 50 grains 
of it with water in an apparatus, in which it was easy fo measure any fluid given off, to the 
Per cent. 
Resins. ez: single Sew. es ii Giese se aes Bede cde vee OED 
PORE Taig has PO Os Oe FE CALS ask a Whew 14.0 
Volatile OU ee es ae oe sc ed ech ee 12.0 
favre oho the Bari. fades. eens i eG es BD 
te) 
ing, too, a considerable proportion of gum, is nevertheless not emulsive. The resin differs 
essentially from that of trae Gamboge, being somewhat less soluble in ether or rectified spirit, 
and possessing a colour somewhat different both in tint and in intensity. Its colour is not 
orange, but rather lemon-yellow; and its solution is so much less intense in tint than that of 
the resin of Siam or true Ceylon Gamboge, that the last two present an equal depth of shade 
when dissolved in ten times as much spirit as the other.”’ 
““ Mr. Royle having expressed an opinion in his Illustrations of the Botany of the Hima- 
layah mountains, that a kind of Gamboge may also be produced by another species of the natu- 
ral family Gustifere, namely, the Xanthochymus pictorius,* it seemed to me desirable to deter. 
mine that point also by an analysis of its resinous exudation, which Mrs. Walker’s specimens, 
have put it in my power to accomplish. 
__ The exudation on the bark of this species is even more different in appearance from true 
Gamboge, than that of the Garcinia cambogia. It forms small tears of a pale greyish-green 
colour, sometimes also pale yellowish-green ; and it is translucent like a resin. It does not 
form an emulsion at all when rubbed with the wet finger. It is pretty hard, and in cold weather 
pulverizable. : 
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 Hebraden- 
dron. 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 agita- 
_ tion, and when evaporated leaves a viscous matter, evidently Arabin, or soluble gum. A small 
- Quantity of fibrous impurities and fleecy particles remains unattacked by the ether and cold 
water. One grain and seven-tenths of the gum resin yielded 1.3 of resin, 0.3 of gum, and 0.2 
Of fibre, that is, 76.5, 17.6, and 5.9 per cent. This result seems to indicate the absence of 
| : * Illustrations, &e. p. 132, part iv,—1834. ee 
