May 1907.] 



263 



Saps and Exudations^ 



devlopment, a contributor to the " Gummi Zeitung" relates that the natives of Mexico 

 have long known that the plant locally known as " Yerba" or " Yule," was a rubber 

 producing plant, The first means employed to extract the rubber was by chewing ; 

 this naturally had to be abandoned as most impracticable. Solvents such as carbon 

 bi-sulphide and naptha extract too much resin, whilst an alkaline and acid 

 treatment is equally unsatisfactory. Subsequently a firm, under the style 

 of " Compania Explotadora de Caucho Mexicana," erected works, and by means of a 

 special process, details of which were kept secret, placed considerable quantities of 

 guayule rubber on the market. The washed and dried gum, however, still contained 

 from 10 to 20 per cent of resins and wax, and from 2 to 6 per cent, of ash, besides 

 this it still retained its characteristic colour. The chief drawback in the presence 

 of the resins, however, was not so much the quantity as their peculiarly objectionable 

 qualities which render the rubber very difficult to work. Proceeding-, however, in 

 their endeavour to improve this raw rubber, the above mentioned company have 

 recently succeeded in preparing guayule rubber of a clear yellowish grey colour, 

 clean and odourless, which works well on the rollers, and upon analysis was found to 

 have the following composition : Resin 1"06 per cent., rubber 98'31 per cent. This 

 product far excels other sorts of guayule rubber, and, it is maintained, is suitable 

 for the production of the finest rubber articles without exception. The writer states 

 that the C. E. de C. M. are taking the necessary steps to place large quantities of 

 this rubber on the market, and hope to produce from their works, now in course of 

 construction in Sattilo (Mexico), about four tons daily. Accordingly, in consequence 

 of the high degree of purity and its excellent physical properties, it is anticipated 

 that this new quality will constitute an article of great importance to the rubber 

 indus try .— India-Rubber Journa I . 



Rubber in East Africa. 



The following Official Reports on the Rubber Industry are cf interest : — 



Zanzibar, June 19th, 1906. 



Sir,— With reference to your Circular (13123) in this series dated April 28th 

 last, I have the honour to transmit herewith two memoranda on the cultivation of 

 rubber in Zanzibar aud in German East Africa, which have been prepared by Mr. 

 Vice-Consul Sinclair and Mr. Vice-Consul Venables, respectively. 



I have etc., 

 (Sigued) BASIL S. CAVE. 



To the Right Hon. Sir Edward Grey, Bart., M.P- 



THE CULTIVATION OF RUBBER IN ZANZIBAR. 



The amount of rubber produced by these islands is at present insignificant, 

 nor, owing to the limited area in which it could be grown, is it ever likely to become 

 an important item of export. All that there is, is derived from Llandolphia vine 

 which is indigenous in the island of Pemba, growing wild in the small forests at 

 the north end of that Island. 



About six years ago the Department of the Director of Agriculture made 

 some nurseries of young plants with the object of planting up the forest-land, native 

 rangers were appointed to prevent the destruction of the vines, and a system of 

 alternately resting parts of the area Avas establislied. The result was that in 1903, 

 2,316 lbs. were brought in as against 763 lbs. in 1899, but owing probably to heavy 

 clove crops, the gathering of which drew away the natives who would otherwise 

 have been employed in collecting rubber, the exports fell to 1,082 lbs. in 1901 aud tq 



816 lbs. in 1905, 



