CURING AND PREPARATION OF RUBBER 95 



Various experiments have been tried for the purpose 

 of finding a more convenient means of fumigating the 

 latex without the necessity of using either paddle or 

 stick, and at the same time maintaining the principle 

 exercised in the use of those implements. The nearest 

 approach to success in this direction has been the in- 

 vention of a tin cylinder revolving over the smoke 

 funnel. This drum is turned slowly by hand, and the 

 latex poured on to it in the same manner as with the 

 paddle or stick. When a thickness of about half an 

 inch has been attained, the sheet is taken off the cylinder 

 and the process repeated. The advantages of this 

 system are that the rubber dries easily, should show a 

 saving in freight charges on account of the lower per- 

 centage of moisture than in pelles or knapsacks, and can 

 be packed for shipment without difficulty. This method, 

 however, has not been adopted to any great extent, in 

 consequence of the opposition of agents and brokers at 

 Manaos and Para, who have refused persistently to give 

 any higher price for it than for pelles or knapsacks con- 

 taining at least 10 per cent., and often 15 per cent., 

 greater percentage of moisture. A large proportion of 

 the owners of rubber-producing properties are so deeply 

 indebted to their agents that they are powerless to re- 

 sent their attitude in this matter, and this explains 

 why no systematic effort has been made to bring the 

 cylinder into more general use in order to manufacture 

 sheet in place of ball rubber. In 1913 some small 

 consignments of sheet rubber made by this process, 

 and shipped to Manaos by the Madeira- Marmore Rail- 

 way Company, were sold at the price then ruling for 

 fine rubber ; but in no case was a higher rate paid 



