STALAGMITIS CAMBOGIOIDES. 
277 
Sensible and Chemical Properties, Gamboge has no 
smell, and scarcely any taste ; when pure * it is of a golden yellow 
colour, opaque, and breaks with a vitreous fracture, its specific 
gravity is 1.221 ; when applied to the flame of a candle it takes fire, 
and burns with a bright, crackling, sparkling flame, with smoke, 
at first it softens, then part melts and drops, the remainder grows 
black, swells, and is changed into a shining friable charcoal. In a 
ladle it slowly softens by heat, but does not smoke, nor melt, but by 
degrees grows black, and changes into a soft, toughish, black mass. 
Gamboge when macerated in water, forms a fine turbid yellow 
solution, and about two-thirds of the gamboge is dissolved ; the 
solution is not precipitated by alcohol, but rendered transparent ; 
oxysulphate of iron strikes with it a pale olive brown, but causes no 
precipitate, nor is it affected by solutions of any of the other 
metallic salts. Alcohol dissolves about 90 per cent. ; the solution 
after settling for some time becomes transparent, and deep yellow, 
water renders the tincture cloudy and bright yellow, but it is long 
before any precipitation takes place. Ether dissolves 60 per cent., 
the solution is transparent, and of a deep golden colour; when 
evaporated on water it leaves an orange coloured resin, which does 
not colour water. Gamboge is also soluble in strong solutions of 
ammonia and potass, forming with them deep red solutions, which 
are not rendered turbid by the addition of water ; with weak acids 
yellow precipitates are produced, which are taken up again by 
adding the acid to excess. Gamboge was separated by Braeonnot 
into one part of cerasine or tragacanthine, and four of a reddish 
brittle resin, which dissolves in spirit of wine and the alkalies : these 
experiments however do not throw any light upon the cathartic 
property of gamboge. 
Medical Properties and Uses. Gamboge is a drastic 
cathartic, acting powerfully on the alimentary canal, in small doses 
it often produces vomiting, hypercatharsis, and other untoward 
symptoms. Orfila has given it a place amongst the acrid poisons, 
and infers from his experiments made on dogs, that it occasions 
death by the powerful local action it exerts, and on the sympathetic 
irritation of the nervous system.f 
Gamboge is used with success as an hydragogue in dropsy, either 
alone, or in combination with cream of tartar or jalap, to quicken 
* It is often mixed with sand and other impurities. — 'Ed, 
f Oriila's Toxicology, vol. ii. p. 24. 
