PLANTATION RUBBER INDUSTRY OF THE EAST. 499 



solved the difficulty. Further East, it met with considerable 

 opposition, and it does not seem to have been adopted at 

 Singapore until tapping on a large scale was begun in 1903. 

 Then, as in other cases, it was found to be the only method 

 practicable. 



Parkin's rubber was prepared in thin circular discs or 

 sheets, which have since been styled biscuits. He advised 

 that they should be about one-eighth of an inch thick, so that 

 the rubber might dry quickly, the biscuit when dry being 

 translucent. Analyses of his rubber proved that it contained 

 about 1 per cent, of moisture, as against the 20 to 30 per 

 cent, of the naturally-coagulated rubber. This manufacture 

 of clean dry rubber was again a revolution in method which 

 is to be attributed to Parkin. Attempts have recently been 

 • made to show that " biscuits " or cakes of rubber were made 

 in the East before Parkin's, the insinuation being that his 

 method had been ante-dated. But the cakes previously made 

 had nothing in common with what is known as " biscuit " 

 rubber, except that they might by accident be circular. When 

 the rubber was allowed to coagulate in the collecting cup, it 

 naturally formed a circular disc, which might be pressed out 

 into a cake thick in the centre and thinning out towards the 

 edges. Some of Trimen's sample collected in 1888 consists 

 of such cakes. Their real nature was described by Ridley in 

 1897, when he stated that " a sample cake of rubber prepared 

 in the Botanic Gardens in 1893, on being cut across in 1897 

 was found to be perfectly sound and elastic, and the inteiior 

 even retained the white colour of the fresh rubbsr." Further 

 evidence is afforded by the brokers' report on Curtis's rubber 

 in 1902. " They say that the sheets should he thinner than 

 yours. What comes from Ceylon is made in the shape of, and 

 about the size of, a dinner plate." (Straits Bulletin, II., p. 24 ) 

 To allege that these were identical with Parkin's biscuits, 

 which were of uniform thickness and quite translucent, is 

 ludicrous. 



Specimens of Parkin's biscuits were exhibited at the 

 Colombo Show of 1898. 



Parkin attempted the centrifugalization of Hevea latex, 

 but failed to effect coagulation. In addition to the Circular 



