SCIENCE PROGRESS 



HISTORICAL SKETCH OF THE 

 CHEMISTRY OF RUBBER 



By S. C. BRADFORD, B.Sc. 

 The Science Museum, South Kensington, London 



Indiarubber, or caoutchouc, is essentially a hydrocarbon, 

 produced from a watery emulsion, or latex, obtained by 

 tapping many tropical and sub-tropical trees, notably Hevea 

 braziliensis . The first rumours of the existence of rubber are 

 said to have reached Europe after the second voyage of 

 Columbus to the New World in 1493-4, during which the 

 natives were found to be in the habit of making playing-balls, 

 bottles, waterproof boots and various other articles of a 

 curious elastic gum. The earliest known reference to the 

 substance occurs in a description by P. Martyr d'Anghiera in 

 1525, of some playing-balls seen by him in Mexico. Father 

 Xavier de Charlevoix describes the ball as of a solid matter, 

 but " extremely porous and light. It soars higher than our 

 balls, falls on the ground, and rebounds much higher than the 

 level of the hand which it quitted ; it falls back again, and 

 rebounds once more, although not to such a height this time, 

 and the height of the bounce gradually diminishes." The 

 Indians in Ecuador and Peru called the material " cahuchu " 

 or " caucho," from which names the term " caoutchouc " was 

 derived. Occasional samples were brought to Europe by 

 travellers to adorn the curiosity cabinets of collectors. It was 

 worth a guinea an ounce. 



In 1 73 1 two expeditions were organised by the Academie des 

 Sciences to determine the figure of the earth. One of these, 

 under the naturalist La Condamine, and Bouguer, an astronomer 

 1 



