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THE INDIA RUBBER WORLD 



[January i, 1910. 



Rubber Culture in the Far East. 



By John C. Willis, M.A., Sc.D* 



THE history of rubber culture in tropical Asia dates from 

 1875, when the authorities at Kew succeeded in convincing 

 the government of India that there were indications of a 

 shortage in rubber supply, as there had been in regard to cin- 

 chona about 15 years earlier, and that it would be wise to get the 

 rubber plants of South America established elsewhere. An ex- 

 pedition was sent, at the expense of the Indian government, to 

 the valley of the Amazon, and succeeded in collecting, among 

 other things, seed of the so-called Para rubber, Hevea Brasilien- 

 sis. These were grown at Kew, and in 1876 the young plants 

 resulting were sent to the East in Wardian cases in charge of a 

 special gardener. The bulk of the plants came to Ceylon, it 

 having been decided that India had no botanic garden in a suit- 

 able climate, but a few went to Singapore and elsewhere. 



A special branch botanic garden was opened in Ceylon, at 

 Henaratgoda, near Colombo, to receive the rubber trees, and 

 about 50 were planted there, the remaining 20 being planted at 

 the chief garden of Peradeniya near Kandy, at an elevation of 

 1,600 feet above the sea, which has on the whole shown itself 

 to be rather too great a height for rapid growth. About 1881 and 

 1882 the plants began to flower, and a few seeds (and cuttings) 

 were distributed, at first to other botanic gardens, and then to 

 planters in the island who had expressed willingness to try the 

 new cultivation. It is from these seeds or cuttings that the few 

 old trees on such estates as Culloden in Ceylon have sprung. 



Very slow progress was made in this way for the next 16 years, 

 but in 1888 the late Dr. Trimen, director of the Ceylon botanic 

 gardens, began to tap the largest of the trees. V-shaped in- 

 cisions were cut with a hammer and chisel, and the milk was 

 allowed to trickle down the stem into a channel made around the 

 base by sticking on a strip of mud, and from this channel it ran 

 into cocoanut shells, where it was simply allowed to dry, and 

 formed a lump of blackish rubber. The tree was tapped once a 

 week for about eight weeks, then given a rest, and again tapped 

 after a few months. It was tapped every second year, and in nine 

 years had given 13 pounds 6 ounces of dry rubber, or an average 

 of 1 ]/ 2 pounds a year. Now this tree was 12 years old when 

 the tapping began, and a yield of l / 2 pound, at the then price 

 of a little over two shillings (50 cents), was not enough to make 

 the cultivation profitable, the more so as this tree was the largest 

 of all, and of a size that most trees only reach in 13-16 years. 



In this condition we found the question on taking up the 

 direction of the Ceylon gardens in 1896, and, feeling convinced 

 that there was a future before rubber, we commenced detailed 

 experiments in 1897. Tapping a large number of trees, so as to 

 get an average result, we found that about 100 pounds of dry 

 rubber might be expected from an acre of trees 10 years old. 

 This at two shillings a pound was enough to show a fair profit, 

 and people began to take up the cultivation from that time. 



One of the most important results of these experiments was 

 the rediscovery of a fact known to the natives of the Amazon, 

 and which is known in the cast as "wound response." At 

 later tappings near to the first the tree yields more milk than at 

 the first bleeding. It is true that this milk is less concentrated 

 so far as the amount of rubber in it is concerned, but it runs 

 so much more freely that more rubber is obtained. This showed 

 clearly the reason of previous unfavorable reports on rubber 

 trees and their yield. Either only one tapping had been made, 

 or the tapping had not been sufficiently frequent to show the 

 wound response. Mr. Parkin, who was in Ceylon in 1898-99, 

 carried out detailed experiments on wound response and fully 

 established the regularity of the phenomenon. 



•Director of the Royal Botanic Gardens, Ceylon. 



Mr. Parkin also worked out the method of preparing biscuit 

 nr sheet is in vogue in the east to the present day. The active 

 constituents of the smoke used in South America having been 

 shown to be acetic acid and creosote, Mr. Parkin showed that the 

 best results were obtained by heating the milk to something over 

 150 degs. Fahr., and coagulating with the calculated quantity 

 of acetic acid in presence of creosote. Planters generally have 

 considered the heating and the creosoting too much trouble, but 

 the making of biscuit or sheet by the aid of acid is most common. 

 Some people allow coagulation to go on naturally by leaving the 

 milk to stand, but this of course simply means that the acid is 

 formed in it by putrefaction. Recently Mr. Kelway Bamber has 

 shown that the heating of the milk destroys the enzyme which 

 it contains, producing a biscuit of the lightest color and one 

 which does not subsequently darken. Good rubber produced in 

 this way has obtained higher prices, and many estates now heat 

 their milk. 



The biscuits obtaining a higher price than the raw rubber 

 dried in cocoanut shells, and the price of rubber rising gener- 

 ally, the industry now began to be rapidly taken up, and there 

 was a great run on the few seeds available in the botanic gardens 

 of Ceylon and of Singapore, where also rubber cultivation was 

 being pushed. Seeds were sold at auction, and in one year 

 realized $10 a thousand. In the course of the following five years, 

 seed began to come in from the trees in private hands, and in 

 annually increasing quantity, until now it is a drug in the market, 

 and proposals are under consideration to crush rubber seeds for 

 the useful oil contained. The price of rubber now began to rise, 

 and it proved that the return could be obtained in less than 10 

 years, and a greater rate than 100 pounds a year, so that the 

 cultivation proved to be extremely profitable. 



The biscuit or sheet form adopted for the eastern rubber, 

 and its clear color and cleanliness, have caused it to meet with 

 great favor, and it has sold at higher prices per pound than the 

 best Amazon rubber. This is often supposed to mark a real 

 superiority, but in reality does not, for it takes ten pounds of the 

 South American rubber to equal eight of cultivated in the actual 

 contents of caoutchouc, and consequently the former is really 

 obtaining the higher price. Why the cultivated rubber should be 

 somewhat lacking in strength and tenacity as compared with the 

 wild is one of the greatest problems of the day. 



Experiments were conducted by the writer and Mr. Kelway 

 Bamber, preparing biscuit without drying, compressing the newly 

 coagulated rubber into a solid mass. In this way a block rubber 

 was turned out resembling the South American, with about 

 10-12 per cent, of water contained in it, and this has been 

 favorably reported on by several manufacturers. Other people 

 think that age of the tree is mainly responsible for the greater 

 strength of South American rubber, but various experiments go 

 against this view. 



It was not long before tapping by means of a hammer and 

 chisel was given up in favor of tapping by knives, usually of the 

 type of a plane. Given a certain amount of bark on the tree, it 

 was obviously necessary to make that last as long as possible, and 

 tapping in V's by chisels was very destructive, so that a given 

 place would not he healed up by the time that one wanted to op- 

 erate on it again. Herringbone or spirally running cuts came in, 

 and the wound response was obtained by shaving off the under 

 side of the old wound. If the sideways-sloping cuts be made about 

 a foot apart, and only one side of the tree be tapped at once, it is 

 found that new bark has fully formed by the time that one re- 

 turns to the cuts first made. 



The early method of producing the rubber in little biscuits 



