ON GAMBOGE. 129 
3d. Nevertheless, by continued boiling, and under the 
influence of a large excess of chlorine, the transformation ' 
does take place; but it is even then only partial. 
Ibid, from Joum. de Chimie Mtdicale. 
ART. XXVIII.— ON GAMBOGE. 
BY DR. BUCHNER. 
This substance is obtained from several plants, as Gar- 
cinia Gambogia, Grambogia Gutta (Linnaeus,) Mangostana 
Gambogia (Gaertner,) Stalagmites gambagioides, Hyperi- 
cum bacciferum and cayanense, natives of the East Indies, 
Siam, and Ceylon, whence it is imported in form of small 
cakes and rolls, or cylindrically-twisted masses. Its com- 
position, according to Christison, is resin, gum, fecula, 
fibrine, and water. The resin must be regarded as the 
chief constituent, and is most abundant in the Ceylon va- 
riety: it contains about 75.5 per cent., and is therefore the 
best for technical purposes, as painting. Powdered gam- 
boge, treated with aether and evaporated, leaves a resin 
which retains a certain portion of the aether, and has a glu- 
tinous property, which it only loses when exposed to a 
very high temperature. The qualities of the resin are those 
characteristic of an acid, and, indeed, those of a fatty acid. 
Its composition gives, as demonstrated, by consuming it 
with oxide of copper, this per centage composition: — 
VOL. IX. — NO. II. 12 
