102 



The Supplement to the Tropical Agriculturist 



ARTIFICIAL INDIA RUBBER. 



AND HOW TO MAKE IT. 



1. Heat together 6 pounds of gelatine and 

 6 pounds of glycerine, until they form a vis- 

 cous mass. Then add 1 pint of linseed oil and 

 continue to heat until the mixture becomes 

 homogeneous. Next add 2h ounces of formal- 

 dehyde or, preferably, of trioxymethylene in 

 powder, previously well mixed with half as 

 much manganese dioxide. Heat until all is dis- 

 solved, then pour into moulds and allow to cool. 



2. The process is the same as above, except 

 that the oil is mixed with 1/10 its weight of 

 sulphur before it is added to the mixture, and 

 that the manganese dioxide may be omitted. 

 The casting, after it has cooled and hardened, 

 is removed from the mold and heated to 30Udeg. 

 F. for an hour, in order to enable the sulphur 

 to act thoroughly on the oil. In this way articles 

 of imitation vulcanised rubber can be made. 



3. This process differs from the last by the 

 incorporation of 8 per cent, of tar, in addition 

 to the 10 per cent, of sulphur with the oil. 

 The toughness of the product may be increased, 

 without affecting its compressibility, by mixing 

 with the mass, while it is still in a viscous 

 state, short fibres of wool, cotton, etc. It is 

 then vulcanised as in process No. 2. — South 

 China Morning Post, Dec. 14. 



RUBBER NOTES. 



Referring to a sample of the rubber Fors- 

 teronia floribunda prepared in Jamaica, the 

 plant of which is said to grow profusely in 

 the limestone district of the island, the " Bul- 

 letin of the Imperial Institute ,! says : The 

 rubber was submitted for commercial valuation 

 to brokers, who reported that it would prob- 

 ably realise 2s. 4d. per lb. in L'ondon, with 

 fine hard Para from South America quoted at 

 3s. 5id. per lb. The result of the examination 

 of this sample of Forsteronia rubber con- 

 firm the conclusions drawn from previous 

 investigations. There is no doubt that the 

 rubber furnished by this vine is of good quality, 

 and, if obtainable in quantity, it would lie 

 readily taleable. Up to the present time the 

 absence of a regular and sufficient supply has 

 been the principal hindrance to the commer- 

 cial exploitation of the rubber from Forsteronia. 



Some particulars showing the rapid develop- 

 ment of Southern Nigeria during the past year 

 have just been published in a Colonial Office 

 report on the district. The quantities and value 

 of rubber exported during the period, compared 

 with the previous year, were: 2,843,800 lb., 

 valued at £245,000, in 1907, and 3,434,300 lb., 

 valued at £307,000, in 1906. The decrease in the 

 export is due, says the report, to the fact that 

 tapping has been prohibited in some of the 

 principal rubber districts. Officers of the 

 Forestry Department give instruction to natives 

 as to the best means of tapping and preparing 

 rubber for the European market. All the rubber 

 exported at present is forest produce. There 

 are large tracts of land in well-situated areas 

 throughout the country suitable for planting 

 Para rubber, and plantations of Para and Fun- 

 tumia Elastica rubber started in recent years in 

 the Central Province are doing well.— (Home and 

 Colonial Mail, Nov. 27th.) 



RECORD PRICE FOR RAM BONG. 



5s. 2d, Per Lb. 



A rubber record for the planting districts of 

 Deli has just been established. The Rambong 

 rubber of the United Serdang (Sumatra) Rubber 

 Plantations, Ltd., prepared according to an ap- 

 proved local method, has just sold, in London, 

 at 5s. 2d. per lb. This is the highest price ever 

 paid in London for Rambong rubber. On another 

 day of the sale fine hard cured Para was quoted 

 at 5s 4d per lb. — Malay Mail, Dec. 28. 



F. M. S. RUBBER EXPORTS. 



Monthly Statement.— The monthly compara- 

 tive statement of cultivated rubber exported 

 from the F.M.S. during 1908 and 1907 has been 

 issued from the office of the Commissioner of 

 Trade and Customs. The statistics of rubber 

 exported are as follows : 



o'Sp 

 a, » o 



o at— cd &d 

 a. c -3 a a. » 



as op a % 



Perak ... 45,669 393,515 224,746 



Selangor ... 208,382 1,872,923 1,073,509 



Negri Sembilan... 62,563 496,228 461,942 

 It will thus be seen that Selangor has an 

 increased output of 799,414 1b., Perak of 168,769 

 lb. and Negri Sembilan of 34,286 lb. The total 

 export for November was 316,614 lb. excluding 

 the Pahang export, and the total increase to 

 date exceeds 1,000,000 lb. It is pointed out that 

 of the rubber exported from Selangor in Nov- 

 ember, 16,136 lb. were produced in Negri Sembi- 

 lan.— Malay Mait, Dec. 11. 



CEARA RUBBER IN CHRISTMAS 

 ISLAND. 



Mr Tait writes :— " The few plants we have 

 here are makiug good growth, having reached a 

 height of 12 feet and a girth of 7 inches, at 3 

 feet from the ground, at nine months old ; from 

 all accounts this seems a fair growth." 



This certainly seems satisfactory considering 

 the peculiar nature of the Christmas Island 

 soil. The whole island consists of three raised 

 coral-reefs rising from sea level to about 1,100 

 feet altitude. Over this coral rock lies a layer of 

 phosphate of alumina which is of some depth 

 near the settlement. During the dry reason, the 

 country gets very dry and owing to the nature 

 of the rock the water sinks through till it ar- 

 rives at the volcanic rock which forms the base 

 of the island at sea level. In such a peculiar 

 soil and climate it is almost surprising that 

 anything grows well, but the whole island is 

 forested with large trees; and vegetables, limes, 

 papaya, and other fruit trees grow well on the 

 rich brown soil near the settlement. Para 

 rubber has been planted as well as ceara, but 

 it is probable that the latter will prove the most 

 suitable. 



H. N. Ridley. 



—Straits Agricultural Bulletin, for Dec. 



