394 SCIENCE PROGRESS 



dispensable raw material. This caoutchouc, known in commerce 

 as " Para," after the Amazon port of that name, has been the 

 recognised standard for fully half a century. It is obtained 

 from the euphorbiaceous tree, Hevea brasiliensis, otherwise 

 known as the Para-rubber tree. Though this is the most 

 important rubber tree, yet several other laticiferous plants 

 furnish commercial caoutchouc — notably among these may be 

 mentioned : Manihot Glaziovii (Ceara rubber) of Eastern 

 Brazil ; Castilloa clastica, of Mexico and Central America ; 

 Funtumia clastica (Lagos rubber), and species of Landolphia 

 of tropical Africa ; Ficus elastica (Rambong) of Assam and 

 Malaya, the familiar " rubber plant " of our greenhouses. At 

 the present time Brazil furnishes about 60 per cent, and Africa 

 30 per cent, of the world's supply. 



The consumption of india-rubber has augmented so rapidly 

 within the last few years, owing largely to the great increase in 

 rubber-tyred vehicles of all kinds, that the supplies are be- 

 coming quite unequal to the demand. Hitherto the world's 

 crop of rubber has come solely from wild sources. In all 

 probability if the cultivation of caoutchouc-yielding trees had 

 been delayed much longer, a rubber famine would be imminent. 

 As it is, there will be a shortage in supplies for a few years 

 to come. Prices for the raw material will rule high, and rubber 

 goods will tend to become dearer or of lower quality through 

 admixtures. The extended use of caoutchouc will be pre- 

 vented, and its much-needed employment for flooring and 

 pavement, where wear and tear is great or silence desired, 

 will have to be postponed. The manufacturers are now paying 

 an unprecedented and quite unforeseen price for this raw 

 material. Fine hard Para is at present quoted in the London 

 market at about 7s. 6d. per lb. 1 A year ago it was only 55. ; in 

 fact, it is now nearly double the average figures for the twenty- 

 five years preceding 1909. In July 1909 the price rose sensation- 

 ally from 6s. to 85. per lb. It was generally expected that it 

 would drop considerably in the autumn with the incoming 

 of the Amazon supplies. These, however, turned out to be 

 smaller than anticipated, and instead of a fall, a rise 

 of another shilling per lb. took place. 2 At present there 

 seems to be a probability of a 75. basis instead of a 55. one 



1 London price, 7s. 6§d., December 24, 1909. 



2 The record figure, gs. 2$<£, was reached in early November, 1909. 



