increase in power in doing what, with washed rubber, can be done 
in a more simple, safe and natural manner. 
MANUFACTURE OF RUBBER. 
1 6. Preliminary Processes. — The various processes through 
which raw rubber passes in conversion to rubber goods were, as a 
whole, very freely shown to me by the British rubber manufacturers. 
Introductions to the leading firms from the War Office and 
Admiralty, who are large consumers of rubber goods, were obtained 
through the Colonial Office, and these, together with sundry 
personal and private introductions, proved to be all that was 
necessary, and I met with great consideration, kindness and 
courtesy from all with whom I came into contact. In a few cases 
there were special and particular processes which were guarded as 
trade secrets, but this tendency to secrecy was in inverse pro- 
portion to the size and importance of the works. The greatest 
interest was shown in plantation rubber and the prospect of a future 
easing of the rubber market by supplies from the East, and the 
manufacturers realise that there can be no antagonism between 
them and the planters, and appreciate the efforts being made to 
bring the producer and consumer into closer touch. 
17. The raw rubber used is of all kinds and qualities, from clean 
pure fine Para to the lowest grades of African rubbers, which are 
sticky, black, full of wood, stones and dirt, and all possible 
adulterations. Fine Para is delivered in balls weighing from five 
or six to a hundred pounds : when cut open the mass is seen to be 
made up of concentric shells from & to £ inch in thickness, the 
rubber is grey and wet and the, successive laminae are marked by 
dark surfaces, showing the stages of successive smoking and 
accumulation of the rubber into the balls. This rubber is never 
dry, but contains water— the amount usually being about 15 per 
cent., but varying from 10 to 20 per cent., and the loss of weight of 
fine Para in washing and drying is due to this water contained in 
it. In the best qualities there is little or no mechanical impurity, 
at most a little surface dirt and grit. 
WASHING RAW RUBBER. 
18. The first thing to be done is to cut these large balls open 
and reduce the largest masses to blocks of five to ten pounds in 
^weight. The rubber is then softened by boiling in water, this is 
done to enable the washing machines to deal with the lumps. 
The rubber is then broken and washed on machines which are 
simple in construction and action, and exactly similar in essentials 
to the rubber-washing machines in use in the Malay Peninsula on 
plantations. 
Each machine consists of a pair of steel rollers with roughen - 
ed faces, revolving at different speeds on horizontal axes, the faces 
of the rollers being in contact or slightly separated from one 
another. The rollers are from one to two feet in length, and 
usually one foot in diameter. The surfaces are roughened with 
grooves cut spirally, or diamond shaped, and of different angles 
