SECTION XV 

 GUM-RESINS 



The gum-resins consist, as their name indicates, chiefly at least of 

 resin and gum. With these constituents, however, there are always 

 associated small quantities of other substances such as volatile oil, 

 bitter principle, enzyme, &c. They are secreted in schizogenous 

 or schizolysigenous ducts, being formed hi the resinogenous layer of 

 the walls of the tapetal cells, and discharged into the ducts in the form 

 of milky liquids which are exuded when the ducts are punctured. 



The resins contained in the gum-resins exhibit in general the 

 characters detailed on pp. 453-4. 



The gum of most of the gum-resins resembles, but is not identical 

 with acacia gum, very possibly it consists of two of more glucosidal 

 acids in varying proportions. It is always accompanied by an enzyme 

 from which it has never yet been freed ; it therefore always contains 

 nitrogen. 



GAMBOGE 



(Cambogia) 



Source, &C. Gamboge is a gum-resin obtained from Garcinia 

 Hanburii, Hooker films (N.O. Gutti ferae), a tree of moderate size found 

 in Cambodia, Siam, and the southern parts of Cochin China. 



The bark of the tree contains in the cortex, as well as in the bast, 

 secretory ducts filled with a yellow, resinous emulsion, the two systems 

 of ducts being connected by transverse canals at the nodes. 



The gamboge is obtained by making, in the rainy season, a spiral 

 cut in the bark from the height of about 3 metres down to the ground. 

 The emulsion wells out and trickles down the incision into a hollow 

 bamboo placed to receive it. From this it is transferred to smaller 

 bamboos ; these are set aside until, in about a month, the gamboge 

 has solidified. It is removed from the bamboo by drying over a fire 

 until the bamboo cracks and can be stripped off. The drug is sold 

 to local collectors, who convey it to Bangkok or Saigon, whence it is 

 exported to Europe, usually via Singapore, 



