RUBBER MANUFACTURE. 



95 



want of ' nerve ' and adverse opinions of a few manufacturers, 

 that when the right conditions are applied, nothing equals the best 

 dried plantation block mixed and vulcanised without previous 

 treatment" 



Analyses of Para rubber produced in various countries are 

 given below : 



* Tropical Agriculturist, Nov. 1904. 



t Bulletin, Imperial Institute, vol. v., No. 3. 



\ Bulletin, Imperial Institute, vol. v., No. 4 



$ "Report on Rubber in the Gold Coast," 1904, Johnson. 



CAOUTCHOUC. 



The percentage of caoutchouc in rubber prepared from 

 cultivated Para trees varies from about 92 to 96.35 per cent. 

 There appears to be practically little difference in the caoutchouc 

 content of rubber prepared from trees varying in age from four 

 to thirty years as shown by the following figures quoted by 

 Kelway Bamber : 



Para Trees, 

 Age in Years. 



4 

 6 



IO tO 12 



3 



Percentage of Caout- 

 chouc in Rubber. 



- 94.58 

 94-75 

 94.60 



- 94-35 



- 93- 2 4 



RESIN. 



The same chemist found very little difference in the per- 

 centage of resin in rubber obtained from cultivated Para trees 

 from four to thirty years of age, this being 2.72 and 2.32 in the 



