210 THE RUBBER TREE BOOK 



When coagulation with acetic and other acids was first 

 employed the latex was poured into numerous small, shallow 

 pans, the coagulated rubber floating upon the tops of these 

 pans in the form of what was called a biscuit, about 9 inches in 

 diameter and J of an inch in thickness. 



It was soon found, however, when large numbers of trees 

 came into bearing, that the number of small pans which would 

 be required was simply enormous. Large coagulating vessels 

 and machinery were introduced, and this had the effect of per- 

 mitting large quantities of rubber to be expeditiously treated. 

 Attention then became directed to working-up the crepe so as 

 to obtain the clearest golden colour possible. 



Smoked rubber, however, has always had its advocates, 

 both among estate managers and manufacturers. Although 

 the same fine colour cannot be secured when rubber is smoked, 

 colour is far from being everything, and indeed there is no doubt 

 but that far too much importance is generally attached to it, 

 putting into the second place far more important qualities. 



The endeavour to free rubber from as much as possible of 

 resin and protein matters, so that it may keep better, is doubt- 

 less founded on a mistaken idea, namely, that the purer the 

 rubber the better the quality. This, it seems to me, is an 

 entire error. Synthetic chemists acknowledge that the great 

 fault and misfortune of the substances which they produce is 

 that they are too pure. The presence of minute quantities of 

 what are regarded as extraneous substances in, for example, 

 natural indigo as opposed to synthetic imitations, secures for 

 it a triumphant superiority in quality. If synthetic rubber is 

 ever in the future put on the market in quantity, I venture to 

 prophesy it will be found to be markedly inferior in quality 

 for the simple reason over-purity. So with rubber; what 

 should be aimed at is early and complete antiseptic treatment 

 of the latex to prevent the action of bacteria setting up fermenta- 

 tions which weaken the nerve of the rubber, and, if allowed to 

 proceed too long without effective check, produce " tackiness." 

 Thorough smoking of entire latex-rubber produces a better 

 rubber than is procurable by washing and tearing and tearing 

 and washing the rubber in the mills till much of the protein 

 matter is removed and the risks of fermentation thereby 

 lessened. 



