484 



RUBBER 



RUBBER (PLANTATION) 



Rubber is obtained from certain trees, climbers, or shrubs, 

 being extracted in the form of white milk or latex by means of 

 incisions or pricks made in the bark (cortex). The supposition 

 that latex is a waste product is doubtless incorrect, for it is main- 

 tained on good grounds that it is associated with certain functions,, 

 as the storage of food, water, and prevention of insect attacks, etc, 



Tapping. The latex flows for a brief time from the said 

 incisions or pricks, being collected in small tins or coconut shells, 

 brought to the factory in enamelled buckets, and strained. In 

 tapping, specially constructed knives or pricking instruments are 

 employed for the purpose. These are sometimes used alternately, 

 but generally the former are most in favour, for they enable the 

 thinnest shaving being pared off the cut surface at each tapping. 

 Pricking instruments are at present generally in disfavour, owing 

 to their liability to injure the cambium and induce woody knobs 

 on the tapping area. Different systems of tapping are employed, 

 some being better adapted than others to certain species and to- 

 trees of different ages; but nearly all are on the principle of what 

 are known as the "herring-bone" or "half-herringbone" (some- 

 times referred to as the "half-spiral") systems. Taking Hevea v 

 the most important rubber tree, the tapping methods employed at 

 present vary as experience may bring one or another into favour, 

 A method in general vogue is to mark the circumference of the 



