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with differences in the amounts of the so-called 
“ impurities ” or non-caoutchouc constituents, which 
are invariably present in the commercial product. 
It is fitting to draw attention in this connection 
to the need which exists for the collaboration of 
the scientific workers in the tropics with those 
immediately attached to the consumers. All inves- 
tigation work is useful but it is of vital importance 
to the plantation rubber industry and eventually to 
the entire British rubber industry to reap the earliest 
fruits of scientific investigation by co-operative work 
in which both producer and consumer can participate. 
The price of raw rubber depends on the laws of 
supply and demand, and consequently any new 
method for the production of raw rubber, even 
though it produces a fundamental improvement in 
the intrinsic quality of the rubber for vulcanization, 
cannot become an economic proposition for the 
producer until a demand by the consumer has 
been established. The latter is, for the most part, 
absolutely unconcerned as to the development of 
new processes on the plantation or new types of 
raw rubber benefitting the planter, but strives rather 
to check any changes in the properties of a raw 
material which he has learnt to know in one form, 
and to handle which he has adapted his machinery. 
Thus a state of - affairs has been created which will 
only be altered by the closest scientific and economic 
co-operation of planter and rubber manufacturer. 
The Americans have already taken an important 
lead in this respect. The Hopkinson process for 
the preparation of desiccated latex or “ L.S.” (latex 
sprayed) rubber, depended, for its establishment on 
an industrial scale, on the consumption for vulcani- 
