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say that crude rubber without any of these impurities would in 

 itself produce a minor revolution in a great many of our india-rubber 

 manufactures. 



As a matter of fact, we already possess a method by which the 

 rubber latex can readily be deprived of its albuminous substances, 

 and this method, known as Biffen's centrifugal method, can easily 

 be applied on the rubber plantation. But it is also well known that 

 the rubber after this treatment will readily coalesce into larger 

 masses, which can then be handled ; it is also tolerably well known 

 that this coalesced rubber differs not immaterially from coagulated 

 rubber by its peculiar flabbiness or lack of " nerve. " I may further 

 state, as the result of recent experiments, that this difference goes 

 even much deeper, and that there is a very remarkable difference 

 in the vulcanisation results obtained with coalesced and coagulated 

 rubber respectively. The difference is certainly not in favour of 

 the coalesced rubber. 



This unquestionably shows that the coagulation process must 

 have an effect upon the rubber, the nature of which is at present 

 only dimly recognised, but which I suggest will ultimately be found 

 to consist in a polymerisation process. 



From this it must not, however, be argued that my plea for re- 

 moving from the rubber latex all albuminous matter will have to be 

 abandoned, but rather that we shall have to find a mode of treating 

 the coalesced — albumen free — rubber in such a way as to impart to 

 it the required condition of polymerisation in an unobjectionable 

 manner. This is a problem which may puzzle the planter, but 

 which is capable of solution by the chemist. Indeed, I have sub- 

 stantial grounds for stating that this problem has already been 

 solved with entire success, and is already practised on one of the 

 largest rubber plantations in Central America. 



The treatment in question not being public property at this 

 moment, it is impossible to do more at present but to state its 

 existence. As to its efficacy there is no doubt. The rubber pro- 

 duced by it is remarkably firm, almost colourless, and beautifully 

 transparent. 



The treatment could, of course, not be extended to scrap rubber, 

 but on a rubber plantation with proper organisation of the collection 

 of the latex the proportion of scrap rubber produced could easily 

 be kept at a very low figure. Nor is there any reason why the 

 planter should not effect the cleaning of the scrap on the planta- 

 tion. The scrap then would still produce a rubber at least equal to 

 the best crude brands now on the market. 



The process of coagulating rubber latex by boiling, described in 

 Mr. Pear's letter, is a piece of unmitigated barbarism invented by 

 niggers, and about on a par with their intelligence. It is merely 

 the solution of a problem by brute force, and it is to be hoped that 

 with the advent of rubber planting this process will recede to the 

 wilderness whence it came. — India-rubber and Gntta Percha 

 Trades Journal, June 23, 1902, 



