44 



THE INDIA RUBBER WORLD 



[October i, 1908. 



Some Notable Exhibits and Mr. Bamber's Processes. 



By Hubert L. Terry. 



Tl 1 E main features of this International Rubber Exhibition 

 have been dealt with by the Editor, and the observations I 

 am about to make refer entirely to the raw rubber exhibits 

 of Ceylon and British Malaya, which occupy two of the most 

 prominent stands in the Hall. Stand is perhaps too plebeian a 

 term to use in connection with the ornate pavilion of Ceylon 

 and the attractive native dwelling of Malaya, but its significance 

 will not be misunderstood. These two exhibits, along with the 

 Dutch colonial exhibits, may, I think, be selected from the bulk 

 of the show as of special interest, embodying as they do the 

 results up to date of the rubber planting industry — one of the 

 newest departures in economic botany. In no way do I wish to 

 belittle the interest attaching to exhibits of raw rubber from 

 the forest — such as the splendid show made by the State of 

 Amazonas. Native rubber, however, is not exactly a novelty, 

 and as the object of the exhibition was declared by the presi- 

 dent in his opening speech to be primarily educational, it is im- 

 portant to lay stress on the greatest novelties in so far as they 

 have an important bearing upon the rubber interest generally. 



Both the Ceylon and the British Malaya stands contained 

 samples of plantation rubber from the most important of the 

 numerous companies located in their respective districts, and it 

 would probably prove more monotonous than instructive to refer 

 to each of these separately, especially as the rubber in its various 

 forms of sheet, block, crepe, worm, etc., is much the same as 

 produced by each company. Botanical exhibits were numerous, 

 and also photographs of general scenery and processes connected 

 with the industry. Samples of such catch crops as indigo and 

 tapioca were also to be seen, and mention should not be omitted 

 of the model estate rubber factory at the Ceylon stand fitted up 

 according to Mr. Kelway Bamber's ideas of how the work of 

 preparing raw rubber for the European market should be carried 

 out. It is, of course, notorious that the procedure on different 

 estates varies considerably, which is not surprising, seeing the 

 novelty of the whole business, and no doubt for some time to 

 come we shall witness great divergencies of opinion. 



There is no doubt, however, that the planters will best serve 

 their own interests if they endeavor to produce rubber of always 

 the same quality, even of the same tint. This latter point may 

 not really be of any importance, but it carries weight with the 

 less enlightened manufacturer. The great complaint in manu- 

 facturing circles up to now has been about the want of uniformity 

 in bulk lots of plantation rubber, and this is of course due to 

 the different procedure adopted on the various estates, and also to 

 the variable procedure of any particular estate. In this respect, 

 therefore, I consider that the detailed proposals made by Mr. 

 Kelway Bamber for the coagulation and preparation of the rub- 

 ber on exact and uniform lines form one of the most important 

 topics brought to the notice of visitors to the exhibition. The 

 variation in the color of the plantation Para from Ceylon and 

 Malaya as shown in the numerous specimens en the stands 

 is very striking, practically all shades from pure white through 

 yellows and browns to black being represented. If Mr. Bamber's 

 process is generally adopted in the future it will mean that a 

 uniform product which is practicallly white will be produced 

 and that rubber manufacturers will be able to order lots amount- 

 ing to several tons with full confidence that the quality will be 

 the same throughout. It would take up too much space to give 

 Mr. Bamber's proposals in anything like detail, but a summary 

 of the main points may be attempted. 



It is important to make a daily testing of the latex from each 

 field in order to determine when the proportion of rubber has 

 fallen to the minimum paying quantity. 



Whatever method of tapping is employed, the trees should be 

 marked in such a way that the bark will be removed system- 

 atically and no irregular patches left which can not be tapped. 

 The best angle is 45°, and this should be maintained by keeping 

 the cuts perfectly parallel from start to finish, and not gradually 

 making them more vertical towards the lower end. 



The knife must be kept perfectly sharp so as to cut and not 

 tear the bark, and immediately after making the cut the channel 

 should be moistened with a very dilute ammonia or formalin 

 solution applied by means of a piece of cloth on a stick; this 

 encourages the flow, delaying the coagulation, and the proportion 

 of scrap rubber is reduced. 



Mr. Bamber advised the use of glass or stoneware cups in 

 preference to sheet iron, as they are more readily cleaned. They 

 are also to be washed before use in a dilute formalin solution 

 made by mixing i part of the ordinary 40 per cent, solution of 

 commerce with 40 parts of water. All the latex collected in the 

 cups is to be strained through fine wire gauze into enamelled or 

 wooden buckets, and on arrival at the factory is again strained 

 into large vats and sampled for its yield of rubber. With regard 

 to the determination of the amount of web rubber per gallon 

 it may be remarked that unless the exact procedure is detailed 

 very variable results will be obtained by different operators, a 

 very similar case being the approximate determination of gluten 

 in flour. With regard to coagulation Mr. Bamber does not seem 

 to favor mechanical methods except where the amount of latex 

 to be treated is only small. His proposals are a high tempera- 

 ture and the use of well diluted acetic acid. 



It is in the coagulation that his most important suggestions 

 arise. He has found that if the latex has steam passed into it 

 until the temperature rises to 180° F. and is maintained at thii 

 heat for three hours, certain organic substances of a proteid 

 nature are destroyed and the rubber subsequently precipitated 

 by acetic acid is quite white and maintains this color after ship- 

 ment. It is mentioned that a solution of wood creosote in spirit 

 can be added during coagulation if desired. Presumably the 

 doctors are not agreed as to the utility or otherwise of this 

 addition of creosote. Samples of perfectly white rubber pre- 

 pared by this oxydase destroying process were to be seen on both 

 the Ceylon and Malaya stands, and it will be interesting to hear 

 what the trade has to say about them. Mr. Bamber's main con- 

 tention is that uniformity in bulk will be secured, and, further, 

 that the colorless rubber will be found of special use in the 

 manufacture of certain goods — such as teats, for example — the 

 white color not being affected by the vulcanization. 



With regard to the subsequent washing and rolling 'processes 

 it is advised after the first rolling to again immerse the rubber 

 sheet in water at 180° F. to ensure complete destruction of the 

 oxydase and the complete removal of all soluble matters on which 

 bacteria and fungi grow. After this the rubber is allowed to 

 contract naturally in cold water out of contact with the air. 



Mr. Bamber is against the too rapid drying of the rubber 

 and remarks that the 10 to 15 per cent, of moisture in Brazilian 

 Para is probably an advantage to it. He does not seem to be 

 enamored of the vacuum drying process, and thinks that the 

 vacuum process if used at all should only come after the natural 

 drying in order to get the rubber quite dry for packing. The 

 best method in his opinion is the use of perfectly dry air which 

 can be obtained easily and economically by a plant of which a 

 working model was shown at the Ceylon stand. It involves the 

 use of a refrigerating plant and a system of pipes which strike 

 one as decidedly ingenious, and for the purpose to be achieved 

 to be devised on soimd scientific lines. 



