Gums, Resins, 



406 



[December, 1911. 



rubber-producing countries has been 

 accorded to this Exhibition, and the 

 large expenditure which has been 

 undertaken by these Governments in 

 order that the conditions surrounding 

 cultivation and preparation of th^ pro- 

 duct shall be worthily preseuted. There 

 is also presented the advantage of 

 seeing the exhibits of Brazil and British 

 Malaya, of Ceylon and India, and the 

 Dutch Colonies and other countries side 

 by side, and this has facilitated the work 

 of those who desire to make comparisons 

 of the manner in which the industry is 

 conducted in various parts of the world. 

 In a special article dealing with the 

 Exhibition an account is given of the 

 present position and the prospects of 

 the rubber industry in the old growing 

 districts, and in those territories, many 

 of them within the British Empire, 

 where rubber has only recently been 

 grown. In addition, arrangements have 

 been made for daily demonstrations of 

 various phases of the work, in order that 

 those who aie unable to visit rubber- 

 growing countries, or are unacquainted 

 with the details of manufacture, may 

 follow the sequence of the work from 

 the earliest stages until the finished 

 product is ready for the market. The 

 decision to take advantage of the 

 presence in London of a large num- 

 ber of those interested in rubber to hold 

 an International Conference was a wise 

 one. This Conference has been attended 

 by planters, merchants, and manufac- 

 turers, and the opportunity they have 

 afforded for the discussion of questions 

 relating to the treatment of the raw 

 rubber and for thevaiious methods of 

 its preparation for the market cannot 

 fail to produce important results. It is 

 only by means of meetings of thi« 

 character, where all those who are 

 interested in the rubber industry may 

 have an opportunity for a free inter- 

 change of ideas, that real and perman- 

 ent progress can be effected. 



It is hoped that by these means the 

 value and importance of the display at 

 the Agricultural Hull may be emphasiz- 

 ed, and that the main facts relating to 

 the rubber industry may be brought 

 more prominently to the notice of the 

 public. 



RUBBER. 



The Lewa Method op Tapping Ceara 



Rubber, 



(Prom the Agricultural Journal of the 

 Mozambique Company, Vol. 1, No, 2, 



June, 1911.) 

 Very considerable areas have been 

 planted with Ceara rubber (Manihot 

 Glaziovii) in this Territory from time to 

 time. The trees grow well even at 

 Beira in sand, but very little success, if 

 any, has attended the attempts in 

 extraction of the rubber on a commercial 

 scale, although the tree has beeu in 

 cultivation in this Territory for the last 

 sixteen years. It therefore appeared 

 desirable that a series of experiments in 

 tapping should be conducted in order to 

 prove, once and for all, whether the 

 Ceara tree can be profitably grown in 

 this country. Accordingly, as mentioned 

 in the last issue of the Journal, the 

 Mozambique Company has initiated a 

 series of experiments at two of its 

 Ceara plantations, viz., Tambarara and 

 Chibabava. At both these properties 

 different systems of tapping are being 

 followed, in order to decide the method 

 of extraction most suitable to the tree 

 in this country. One of these is known 

 as the Lewa method, which was first 

 discovered about ten years ago by a 

 planter named Kohler in German East 

 Africa, and is named after the Lewa 

 plantation near Tanca. As this system 

 has been successfully and almost ex- 

 clusively employed in German East 

 Africa for the last ten or eleven years, a 

 description of the method, it is thought, 

 m^y be of interest to those possessing 

 Ceara plantations in this Territory. 



The Ceara tree is of a different nature 

 to Para, aud the methods of tapping 

 Para by excision of the bark have not, 

 as a rule, been found successful in the 

 case of Ceara. The Ceara tree has 

 a thinner and softer cortex, and its 

 removal by paling is a more difficult 

 matter and requires very great care 

 in the operation. The knives even 

 in the best condition often tear pieces 

 of the bark away and leave the 

 wood exposed, damaging the tree. 

 Further, in most parts of East Africa 

 the latex does not flow so freely as in 

 certain other countries, and without 

 the use of dilute ammonia only approx- 

 imately 50 % of the latex can be collected 

 in liquid form, in some cases not so 

 much, the balance coagulating on the 

 tree in the cuts. The Lewa method of 

 incision t heref ore appears better adapted 

 to the physical nature of the tree than 

 the various methods of excision followed 



