GUMS. 
15 
CHAPTER I. 
GUMS, RESINS, CAOUTCHOUCS, GUTTA¬ 
PERCHAS, AND SIMILAR SUBSTANCES. 
The products here dealt with may be regarded as some¬ 
what similar in origin, arising from the drying or coagulation 
of saps or excretions from the plant, or obtained from them 
by distillation or otherwise. They must be further sub¬ 
divided, and the following grouping is convenient for the 
purpose :— 
1. Gums (in the strict sense). 
2. Resins. 
3. Caoutchoucs or Indiarubbers and Guttaperchas. 
4. Miscellaneous, including Camphors, &c. 
Sub-section 1, Gums. 
Gums are the product of disintegration of the internal 
tissues or cells of plants, and exude at the outer surface, 
usually on the bark of the stem. They are especially 
common in the plants of dry countries, such as Egypt, 
Arabia, Persia, India, Australia. They are collected in 
many cases from the natural exudations only, but perhaps 
more commonly from exudations at wounds purposely made 
in the bark. Collection is usually carried on in the dry 
weather, after the end of the rains. 
Gums swell or dissolve in water, but are insoluble in 
alcohol or ether. They are thus distinguished from resins, 
but in commercial use the two classes of products are 
confused, some gums being termed resins, and vice versa. 
Gums are usually brought to market in the form assumed 
by the exudations upon the trees, or in balls and other 
