Gums, Resins, 



3 IS 



[APRIL, 1909. 



lay stress of 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 import- 

 ant 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 Euiopean market should 

 be carried out. It is, of course, noto- 

 rious 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 o y wn 

 interests if they endeavour 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 Avith the less enlightened 

 manufacturer. The great complaint in 

 manufacturing 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 pro- 

 cedure of any particular estate. In this 

 respect, therefore, I consider that the 

 detailed proposals made by Mr. Kelway 

 Bamber for the coagulation and pre- 

 paration of the rubber on exact and 

 uniform lines form one of the most 

 important topics brought to the notice 

 of visitors to the exhibition. The varia- 

 tion in the colour of the plantation Para 

 from Ceylon and Malaya as shown in the 

 numerous specimens on the stands is 

 very striking, practically all shade 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 practically white will 

 be produced, and that rubber manufac- 

 turers 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 systematically and no irregular 

 patches left which cannot 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, delay- 

 ing 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 one part of the ordinary 40 per 

 cent, solution of commerce with 40 parts 

 of water. All the latex collected iu the 

 cups is to be strained through fine wire 

 gauze into enamelled or wooden buckets, 

 and on arrival at the factoty 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 de- 

 tailed, very variable results will be 

 obtained by different operators, a very 

 similar case being the approximate de- 

 termination of gluten in flour. With 

 regard to coagulation Mr. Bamber does 

 not seem to favour mechanical methods 

 except where the amount of latex to be 

 treated is only small. His proposals are 

 a high temperature 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 arises to 

 180° F., and is maintained at this heat 

 for three hours, certain organic sub- 

 stances of a proteid nature are destroyed, 

 and the rubber subsequently precipitat- 

 ed by acetic acid is quite white and 

 maintains this colour after shipment. 

 It is mentioned that a solution of wood 

 creosote in spirit can be added during 

 coagulation if desired. Presumably the 



