238 



THE INDIA RUBBER WORLD 



[February, 1, 1912. 



have become indebted become callous and openly state that they 

 prefer to go to jail than to complete their contracts." He sug- 

 gests that contracts should be completed after a sentence of im- 

 prisonment has been served for breach, and that others engaged 

 in the same industry should be debarred from employing such 

 men until they have done so, pointing out that such a remedy is 

 recognized in the existing Immigration Law of the colony 

 and that some such provision exists in Surinam. He suggests 

 that bleeders should be registered by a government department. 



THE BLEEDING REGUL,\TIONS. 

 Mr. Edwards referred in his letter to the bleeding of trees : 

 The restriction in the regulations as to bleeding is positive, but 

 from the information received it is clear that any bleeding, often 

 repeated, kills the trees eventually, he says. The primitive 

 method of bleeding with a cutlass, done under any restrictions, 

 is likely to wound the tree to such an extent that rot and decay 

 set in. On the other hand statements have been made by old 

 bleeders that they have seen trees that have been bled right 

 round still in good health and yielding latex Tre^.. This,;ques- 



• tion is of great importance and all the available informafioii on 



i the matter should be gathered. 



The government has replied that with the assistance of Pro- 



■ fessor Harrison, director of Science & Agriculture, the acting 

 governor is causing inquiries to be made of all persons or scien- 

 tific institutions from whom it is thought reliable information as 

 to the life history of the balata tree may be obtained. 



THE AMERICAN EXHIBITION. THE COLONY TO BE 

 REPRESENTED. 

 j ; .^t a meeting of the Permanent Exhibition Committee, held on 

 k-Pecember 6, it was resolved that the colony should be repre- 

 sented at the Rubber Exhibition, to be held in New York in 

 1912 ; but, in order to effect economy, if possible, it was resolved 

 to communicate with the secretary of the Permanent Exhibition 

 Committee of Trinidad, to ascertain whether that committee was 

 prepared to consider a joint exhibit. The proposal that the colony 

 should be represented at all events provoked very little discus- 

 sion ; the desirabilty of the suggestion being manifest to all. 

 Indeed, it was pointed out that the development of the industry 

 is likely to spring to a much greater extent from the United 

 States, both from the point of view of supplying capital and of 

 providing a market. The fear is entertained here that the 

 superior attractions of the Eastern plantation rubber industry are 

 likely to withdraw the attention of British capitalists from the 

 possibilties of this colony as a profitable field for the investment 

 of capital in rubber. At all events, the colony is going to see 

 what it can do by bringing its attractions before the American 

 rubber interests. It was pointed out at the meeting to which I 

 have referred that the colony's expenses at the British exhibition 

 amounted to £101 3s. lid. 



RUBBER TAPPING. INTERESTING EXPERIMENTS. 

 A report has been published by the Department of Agriculture, 

 of the results of a long series of experiments, carried out on 

 wild Sapiuni Jenmani trees. The tappings have proceeded 

 over a period of two years. The results are said to be valuable 

 from a scientific point of view. "It must be pointed out and 

 emphasized that the results apply only to old Sapium Jenmani, 

 growing in conditions such as obtain on river banks" ; says the 

 report, "they do not justify any conclusion being drawn as to the 

 behavior of young trees on plantations on higher and drained 

 lands." 



The following are the results of the experiments : "The trees 

 yielded latex very freely when first tapped, and produced rubber 

 of very high quality, not subject to 'tackiness.' The yields of 

 latex and consequently of rubber rapidly fell ofif during successive 

 tappings and the rubber obtained from the tappings was subject 

 to 'tackiness.' This tendency increased during subsequent tap- 

 pings ; until some, if not all. of the trees, when exhausted by 



frequent tappings, yielded latex from which coagulated rubber was 

 not obtainable. It was noted that the tapped part of the trees 

 ran practically dry of latex after three to six successive parings. 

 There were no signs of wound response. When the lower part 

 of the trunk of a repeatedly tapped tree was practically exhausted 

 of rubber-yielding latex, the higher parts of the trunk yielded 

 latex in relatively large quantity, and while the rubber from the 

 latex of the lower part of the tree might be very 'tacky,' or more 

 or less resinous and coagulable with difficulty, that yielded by 

 the upper part, was of very good quality. The wounds made on 

 the bark of the tree during tapping, were found to heal very 

 slowly and unsatisfactorily. The tendency to 'tackiness' was 

 much more noticeable in biscuits prepared from the latex, than 

 in carefully prepared self-coagulated 'scrap.' " 



The report concludes with some interesting figures : "During 

 a period of two years the yield of dry rubber from mature Sapium 

 Jenmani trees of various sizes from 30 to 92 inches in girth, at 

 three feet from the ground — the great majority of them, however, 

 measuring between 40 and 90 inches in circumference — was 15.33 

 ounces per tree. The trees were tapped up to a height of six feet 

 or seven feet from the ground, and were bled to practical dry- 

 ness. The proportion of rubber appeared to vary considerably. 

 The latex obtained in 1905 yielded about 18 per cent, of dry 

 rubber, that of two trees tapped for the first time in 1910 con- 

 tained 15 per cent; while that yielded by trees which had been 

 subjected to tappings during several periods contained about 

 11 per cent." 



The percentages of "rubber" in the dry rubber of the biscuits 

 of the various qualities, was found by analysis to be: 



"Rubber" in 

 dry rubber. 



Excellent rubber from first period 94.5% 



Weak, inclined to be tacky, from 2nd to 3rd periods 93.6% 



Quite soft, and very tacky, from 3rd period 92.4% 



Soft, tacky, resinous, coagulated mass from 4th period.... 51.3% 



( The proportion of "chemically pure" rubber extracted on 

 analysis varied in similar fashion.) 



The Government Economic Biologist, lately appointed, has 

 been turning his attention to the insects and pests attacking 

 rubber in the colony, and planters have the consoling assurance 

 that his researches have not, up to the present, been productive 

 of very alarming results. He reports that a species of scale 

 insects seems to be the most prevalent, which attacks the younger 

 shoots, giving them a characteristically "warty" appearance, and 

 often causing their death. Careful investigation is advised, and 

 the appearance of these indications is to be resisted by the 

 timely application of a good rosin compound wash, which is 

 guaranteed to prove effective. Another scale is said to be fairly 

 prevalent, but does not do much mischief, and can also be dealt 

 with by means of the rosin wash. Ants occasionally do con- 

 siderable damage to young trees, sometimes, completely defolia- 

 ting them. The method of prevention advised in this case is to 

 trace the olifenders to their lair. Having found their nest, all 

 holes leading to it are to be closed with earth or clay ; several 

 holes are then to be bored to a depth of about half a foot, in the 

 centre of the nest, and about two ounces of carbon bisulphide 

 should be poured into each hole, the hole being plugged with 

 earth. Such methods are warranted to consign these trouble- 

 some pests to a place where insects cease from troubling. 



The larvae of two varieties of hawk moth commit depreda- 

 tions on the leaves of young trees, but they may be kept in check 

 by hand picking, being easily discernible and not numerous. A 

 species of locust has done some damage, but these also may be 

 caught by hand, and are not sufficiently numerous at present to 

 create any anxiety. The rubber planter here at present has 

 little cause for uneasiness in this respect, and a little vigilance 

 will secure him immunitv from such troubles. 



