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The proportion of resin is higher than with Brazilian, this may 
be due to overheating during the smoking process, which, as you 
mention, was the case, 
I send you a sample of washed and dried Caoutchouc and a cake 
of the manufactured article made of the same material, marked “ST 
A second cake marked “P.” is made of Brazilian Rubber. As you 
will see the quality marked “S” is just as good as the other one. 
Kindly communicate to Mr. Ridley and Mr. Derry the above 
mentioned results. 
I am, 
Yours etc., 
(Signed.) Ad. PRINZHORN. 
As already remarked, the inexperience of our operators was 
against the preparation of good marketable samples but the reports 
agree that the rubber prepared by smoking is only a little below fine 
hard para which, we suspect, is the produce of a species of Hevea 
which is local and is not the common Para tree of Eastern Brazil. 
These reports confirm the opinion we hold of the importance of 
developing well-matured trees. The difference in the physical tests 
and, appearance of rubber from young or old trees coagulated with 
such re-agents as Acetic acid is not, or scarcely, perceptible, but 
under the smoking process the superior strength and elasticity of the 
resulting rubber from old trees is manifest. 
It should be referred to in conclusion — that so far, (and probably 
is will be so for the next few years), plantation rubber has not 
had to stand the test of its keeping qualities in the crude state. This, 
we are convinced, will be improved by creosoting or smoking. Un- 
smoked rubber of any grade perishes much earlier than smoked 
samples. 
In smoking biscuits or sheets such rubber should be surface-dry 
before smoking as smoke quickly darkens wet rubber but if surface- 
dry, the light pale colour is still retained provided that the smoke is 
dry, and the curing house thoroughly well ventilated so that the 
smoke escapes freely. Retained smoke soon becomes overcharged 
with moisture. The following reports have been received on rubber 
smoke cured in the Singapore Garden : — 
(To H. N. Ridley, Esq., Singapore Botanic Gardens). 
Dear Sir, 
We now have pleasure in enclosing report and valuations of the 
>, two cases lightly smoked sheet rubber ex S.S. “Egypt.” 
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