GUMS, RESINS , CAOUTCHOUCS 
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divided into resins proper, gum-resins which contain a 
mixture of gum and resin, and balsams , which are more 
or less fluid, either fluid resins, or resins dissolved in 
ethereal oils. The chief balsams are those of the Coniferae 
(Abies, Pinus, Larix, &c.), commonly known as turpentines. 
When distilled, common resin or rosin is left, and oil of 
turpentine (often known as, and confused with, true turpen- 
tine) passes over. Many Burseraceae, especially Canarium, 
yield good balsams (< elemis ), and others are given by species 
of Toluifera, Liquidambar, Styrax, Pistacia, Commiphora, 
Copaifera, Dipterocarpus, &c. Among the important gum- 
resins are gamboge (Garcinia), frankincense (Boswellia), 
and the resins of many species of Ferula, Dorema, Calo- 
phyllum, Convolvulus, &c. Of true resins, common resin, 
some forms of which are known as white pitch and colo- 
phony, is obtained from turpentines by distillation, the 
hard copals or animes are derived from species of Trachy- 
lobium, Hymenaea, Agathis, &c., the dammars from Shorea 
and other Dipterocarpaceae, Canarium and other Burse- 
raceae, &c. ; other important resin-yielding genera are 
Guaiacum, Xanthorrhea, Rhus (Japanese lacquer), &c. 
In many species of Croton, Ficus, Butea, Schleichera, &c., 
a resin is formed as an excretion from the skin of the 
lac insect, and forms the lac of East Indian commerce. 
The chief use of resins is in the manufacture of varnishes, 
i.e. solutions of resins in oil of turpentine, alcohol, or other 
solvents. Many resins are used in medicine, in lacquer- 
work, &c. 
Kinos are resin-like substances in appearance, but 
soluble in water, astringent, and used in medicine and in 
tanning. The chief are yielded by species of Pterocarpus, 
Butea, and Eucalyptus. 
Caoutchouc occurs in suspension in the latex of many 
trees, especially Euphorbiaceae and Moraceae. When the 
bark is wounded the latex flows out and a mass of india- 
rubber is formed by the union of the caoutchouc particles, 
either by simple drying (with or without gentle heat) or by 
the use of acetic acid or other coagulants. The most 
important rubbers are Para (Hevea), Panama (Castilloa), 
Ceara (Manihot), African (Landoiphia), and Lagos (Fun- 
