UTILISATION OF RUBBER ^ 



until after 1850. The discovery of the important West 

 African rubber tree Fimtumia elastica, Stapf (also known 

 as Kickxia elastica, Preuss), is of very recent date, as it 

 was first found in the Cameroons by Dr. Preuss in 1898. 

 The rubber from this tree had been previously attributed 

 to the allied species Funtumia africana, Stapf {Kickxia 

 africana, Benth.). 



Utilisation of Rubber. — The earliest use of rubber 

 was made by the natives of Central and South America, 

 who employed the latex for rendering boots and fabrics 

 waterproof and for the manufactiu'e of vessels of different 

 kinds. For many years after its discovery caoutchouc 

 was regarded in Europe merely as a curiosity, but in 

 1770 Priestley suggested that it might be employed for 

 erasing pencil marks from paper, a use which led to 

 the adoption of the name indiarubber for the product. 

 Its first important industrial application was the process 

 invented by Macintosh in 1820 for the production of 

 "vv^iterproof fabrics ; but it was the discovery, in 1839, 

 of tlie process of vulcanisation by Goodyear in America 

 which laid the foundation of the modern rubber industry. 

 Goodyear found that if rubber is heated with sulphur, \ 

 a change takes place, with the result that the material 

 afterwards retains its elasticity through a much wider I 

 range of temperature than before. He subsequently 

 discovered that the final effect of this treatment of 

 rubber with sulphur was the production of the hardi 

 material known as ebonite or vulcanite. Specimens 

 of vulcanised rubber prepared by Goodyear were brought 

 to England in 1842, and Hancock, after seeing these, 

 discovered independently that the change could be 

 produced by heating a mixtuie of rubber and sulphur, 

 or by immersing rubber in molten sulphur. These 

 discoveries were of the highest importance, as they 

 rendered it possible to utilise rubber for a large number ^ 

 of technical purposes for which the unvulcanised pro- 

 duct was unsuitable, and as a result the use of rubber 

 has steadily extended. During recent years the rubber 

 manufacturing industry has assumed very large pro- j 

 portions, principall}^ on account of the enormous demand 

 for tyres, for motor-cars, carriages, and cycles. 



Cultivation of Rubber Plants. — Until recently rubber ] 

 was obtained exclusively from wild plants growing in ' 



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