

CAMBOGIA. 85 



several months. When it first issues from the tree, it is a yellowish 

 fluid, which after passing through a viscid state hardens into the 

 gamboge of commerce. 



The trees grow both in the valleys and on the mountains and will 

 yield on an average in one season enough to fill three joints of bamboo 

 20 inches in length by li inches in diameter. The tree appears to 

 suffer no injury provided the tapping is not more frequent than every 

 other year.^ 



According to Dr. Jamie of Singapore, the gamboge-ti-ee grows most 

 luxuriantly in the dense jungles. The best time for collecting is from 

 February to March or April. The trees, the larger the better, are 

 wounded by a parang or chopping-knife, in various pai-ts of the trunk 

 and large branches, when prepared bamboos are inserted between the 

 root and the bark of the trees. The bamboo cylinders being tied or in- 

 serted, are examined daily till filled, which generally takes from 15 to 

 30 days. Then the bamboos are taken to a fire, over which they are 

 gradually rotated till the water in the gum-resin is evaporated and it 

 gets sufficiently hard to allow of the bamboo being torn off.'^ 



Description — The drug arrives in the form of sticks or cylinders 1 

 to 2h inches in diameter, and 4 to 8 inches in lengtli, striated lengthwise 

 with impressions from the inside of the bamboo. Often the sticks are 

 agglutinated, or folded, or the drug is in compressed or in shapeless 

 masses. It is when good of a rich brownish orange tint, dense and 

 homogeneous, breaking easily with a conchoidal fracture, scarcely trans- 

 lucent even in thin splinters. Touched with water it instantly foims a 

 yellow emulsion. Triturated in a mortar it affords a biilliant yellow 

 powder, slightly odorous. Gamboge has a disagreeable acrid taste. 



Much of the gamboge shipped to Europe is of inferior quality, being 

 of a brownish hue or exhibiting when broken a rough, granular, bubbly 

 surface. Sometimes it arrives imperfectly dried and still soft. 



Chemical Composition — Gamboge consists of a mixture of resin 

 with 15 to 20 per cent, of gum. The resin dissolves easily in alcohol, 

 forming a clear liquid of fine yellowish-red hue, and not decidedly acid 

 reaction. It forms darker-coloured solutions witli ammonia or the fixed 

 alkalis, and a copious precipitate with basic acetate of lead. Perchloride 

 of iron colours a solution of the resin deep blackish brown. 



By fusing purified gamboge resin with potash, Hlasiwetz and Barth 

 (1866) obtained acetic acid and other acids of the same series, together 

 with 2Moro(jluciii, (J'B^iOHf, i?yrotartaric acid, CffO^ SiW^ iswvitinic 

 acid, C«ffCH'(COOH)^ 



The gum which we obtained to the extent of 15 8 per cent, by 

 completely exhausting gamboge with alcohol and ether, was found 

 readily soluble in water. The solution does not redden litmus, and is 

 not precipitated by neutral acetate of lead, nor by perchloride of iron, 

 nor by silicate or biborate of sodium. It is therefore not identical 

 with gum arable. 



Commerce — The drug finds its way to Europe from Camboja by 

 Singapore, Bangkok, or Saigon. In 1877 the first place exported 240 



^ Spenser St. John, Life in the Forests of ■* Fharm. Journ. iv. (1874) 803. 



the Far Eaut, Lond. 1862. ii. 272. 



