Vol. X. No. 237. 



THE AGRICULTURAL NEWS. 



171 





RUBBER NOTES 



INTERNATIONAL RUBBER AND ALLIED 



TRADES EXHIBITION. 



The last number but one of the Agi ii-ultural Xtws con- 

 tained an announcement that the Kolonial Wirtschaitliches 

 Komitee of Berlin is offering its gold medal, for services ren- 

 dered to colonial economic development, at the above exhibi- 

 tion, for the best process of obtaining and preparing rubber 

 from Manihot and Funtumia. It is learned that Ficus rubber 

 has been added, and the following rules for the competition 

 are now issued : — 



1. The comi)etitors shall .show- their methods at the 

 Exhibition by samples of prepared rubber, which shall weigh 

 not less than 10 !b,, also .samples of the tools and appliances, 

 together with full and detailed descriptions and drawings or 

 photographs showing the processes by wliicli the ruliber is 

 extracted, coagulated and prepared. 



2. The competing exhibits will be lirought together in 

 one collection, and located in any part of the Exhibition that 

 the management may deem suitable. 



3. Not only private persons, but also companies and 

 institutions may compete, provided they or the Government 

 of the country in which they are domiciled are exhibiting in 

 the ordinary way. Such Governments are also eligible to 

 compete. 



4. The medal will lie the absolute property of the 

 successful exhibitor, and will be presented to him at the 

 International Rubber Exhibition Dinner, which will be held 

 in London during the course of the Exhibition. 



5. Judges have the right of testing every sample, tool 

 or appliance; their decision shall be final and without appeal. 



6. The management of the Exhibition will take care to 

 protect the exhibits, but will not be responsible for loss or 

 damage 



All entries must be made to the Award Committee, 

 International Rubber and Allied Trades Exhibition, Ltd., 

 75, Chancery Lane, London, W.C.by Thursday night, June 1, 

 1911. Entries should be sent l)y registered post, or be 

 delivered by hand, so that a receipt may be given for them. 

 Exhibits for competition must be sent direct to the Award 

 Committee, Koyal Agricultural Hall, Islington, London, N., 

 but should not reach that building before June 15, and not 

 later than June 20. Carriage must be paid on all exhil>its. 



TIME OF FLOW OF La. TEX AND YIELD 



OF RUBBER. 



The length of time which latex flows from a freshly made 

 cut has a direct connexion with the yields on estates. It is 

 unfortunate that the latex flows only for minutes, instead of 

 hours. The length of time which latex flows is dependent 

 upon many factors; some — the anatomy of the plant, the tissue 

 tension and atmospheric pressure — are beyond our control, 

 whilst others, such as water content of the latex, can be 

 modified during collecting operations. The time is shortened 

 by the dryness of the air, by heat and by sunlight. The 



former often necessitates the stopping of tapping operations 

 in drj' seasons, but can be partially controlled by the use of 

 water from drip tins, to retard the coagulation of latex at the 

 cut ends of the latex tubes. The bad effects of heat and sun- 

 light can to some extent be minimized by choosing certain 

 times of the day for tapping, and by combining this with 

 compass tapping, while some intercrop can shade the trunks 

 of the trees. Atmospheric humidity depends almost entirely 

 upon the location of the estate, but something might be done 

 to influence this in normally dry districts, by the retention of 

 a definite proportion of the original forest to serve as a wind- 

 break, or planting wind-belts or bushy intercrops that will 

 have a similar effect. By thus impeding the circulation of 

 air, there will be a partial retention of moisture that has come 

 from the soil and from the leaves. 



In some reports of tapping on the Amazon, reference is 

 made to the renewal of the flow by picking oft' the scrap before 

 it has become too thick; a second, and even a third flow, can 

 sometimes be obtained by this means. Hart reported this in 

 some of his Trinidad experiments, and Vernet also appears 

 to have ' refreshed' the cuts twice on a certain day, with 

 a gradually decreasing yield. In the.se experiments time 

 enters as a factor, the interval being sufficiently long to permit 

 of an accumulation of latex, of varying richness in caoutchouc, 

 towards the cut ends of the latex tubes. 



The subject is not so trivial as it may on first consider- 

 ation appear. The larger the quantity of latex obtained per 

 incision, the greater is the bark economy effected. So far, 

 the only feasible operation appears to be to maintain open 

 latex tubes by the pas.sage of water alone, or water containing 

 ammonia, along the tapped surfaces as soon as the flow begins 

 to lessen. {The India-Rubber Journal, April 1, 1911, p. 2i.) 



MOLASSES AS F'OOD FOR STOCK. 



The Bullet in of tlie Bureau of Aijricultural Intelligence 

 and of Plant Diseases. International Institute of Agriculture, 

 No. 2, pp. 307 and 308, contains reviews of three papers that 

 have appeared recently in connexion with the use of molasses 

 as food for stock. In the first of these, there is reference to 

 a proposal that has been made for the protection of the trade 

 in molasses for cattle-feeding in Germany. It appears that 

 the doubtful value of many of the molasses feeding stuff's in 

 that country has led farmers to distrust such foods to a very 

 large extent. To correct this tendency, it is propo.sed that 

 pure products containing molasses should be protected by 

 adding the patented name Molassin to the names of the other 

 substances in the mixture. The suggestion has also been 

 made that a special commission should be appointed for the 

 purpose of determining the guaranteed content of molasses 

 and sugar in the products protected in this way. 



The second paper has relation to feeding experiments 

 with draft horses in Sweden, using molasses and Molassin, 

 which in this case is a mixture containing four-fifths molai3ses 

 and one-fifth pulverized peat. It was found that there was 

 no advantage in the employment of the Molassin in the place 

 of the molasses, as regards nutrition. An interesting indica- 

 tion was received to the effect that molasses, at any rate in 

 limited quantities, gives in draft horses a greater amount 

 of energy than was hitherto believed to be obtainable. The 

 third paper describes experiments, with tank steamer molasses 

 from Porto Rico, in regard to the digestibility of hay and of 

 hay and concentrated foods. In the result, it was found that 

 small amounts of molasses usually caused as much depression 

 of the digestibility of the hay as large amounts, the loss hav- 

 ing an average value of S per cent. 



