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yet been satisfactorily explained. The only data we have to base 
any theory on are, that Brazilian Para rubber comes from trees 
of much greater age than those which give the plantation product 
rubber. We have however trees over 30 years old in the East and 
the rubber from these does not show very markedly that it has the 
brazilian properties of elasticity and resilience. 
Plantation rubber to describe methods briefly is coagulated soon 
after leaving the tree and then pressed by rolling or simple pressure 
until a large proportion of the water is expelled the partially dry 
rubber is then dried by hanging in hot dry air and is not packed in 
for shipment until contains a very small proportion generally less 
than 2 % of water. On many Estates the rubber is during the 
rolling process submitted to a constant stream of water which has 
the effect of washing out the resins and proteids. 
The Brazilian method is to coagulate in thin layers by means 
of smoke which contains acetic Acid which induces, coagulation 
and creosote, which prevents the growth of organisms causing 
tackiness and putrefaction. No steps are taken to eliminate the 
water and the mass of coagulated films contain 15 to 20 per cent, 
of moisture. 
The method of coagulating by thin films impregnated by smoke 
produces a mass which has in itself an automatic pressure. Each 
film on contracting acts as a very thin tight rubber bandage and 
thought it is difficult to estimate it is probable that the pressure 
throughout the mass is considerable and might be represented by 
considerable number of pounds per square inch. 
The Brazilian differs in its preparation from the Eastern plantation 
rubber chiefly in regard to its being coagulated in thin films without 
extracting the water and antisepticized by means of creosote in the 
smoke to which it is submitted. 
Whether the antiseptic substance can be added as satisfactorily 
to the liquid latex as it is when deposited from the smoke requires 
a careful series of observations. I am inclined to think that it 
can be more intimately incorporated when mixed with the latex 
before coagulation, than when ‘applied during or after the process 
of coagulation. 
The Exhibits of rubber with the exception of the block shown 
by the Lanadron Company and some similar blocks exhibited by 
Mr. C. O. Macadam of Culloden Estate, Kalutara, Ceylon, included 
nothing’new. Biscuits, t Sheet, Crepe, and Scrap, all of very fine 
quality were shown from Ceylon «and Federated Malay States. 
The size of the Exhibits sent by planters from the latter who had 
not limited themselves to the 5 lbs. which was given as the smallest 
amount admissible, gave the benches where the Malayan rubber 
was shown a more imposing appearance, than the meagre show of 
some of the Ceylon Exhibits in which only a very few biscuits or a 
small amount of sheet or crepe was sent. 
The most interesting result of the judging from a Ceylon and 
