January i, 1905.] 



THE INDIA RUBBER WORLD 



115 



It has taken much work to protect this tree against the many 

 enemies it seems to have in Kamerun, for which reason it is 

 doubtful if this tree can be an object for farming on a large 

 scale in Kamerun, even if it should give a satisfactory amount 

 of rubber. 



Considering that'the trees with which tliose experiments were 

 made are quite strangers to Africa, it is no wonder that the re- 

 sult was not good. As we now have such a splendid tree as the 

 Kickxia elastica. growing wild in the country, this ought first 

 of all be selected for planting. On many farms in Kamerun the 

 Kickxia is now planted as a shade tree, and has shown itself 

 hardy and fairly quick growing. If the planted trees turn out 

 to give as much rubber as in a wild condition, a better rubber 

 tree for cultivation in West Africa cannot be found. We ex- 

 pect to be able to begin to tap them when they are eignt years 

 old. A wild growing Kickxia of ordinary size gives, without 

 injury to its growth, one kilogram [ = 2.2 pounds] of rubber 

 yearly. 



It is high time that the colonies in Africa by extensive farm- 

 ing replace the destroyed rubber trees; otherwise there will in 

 a few years be no African rubber to meet the ever increasing 

 demand. Very likely the Germans in Kamerun will take the 

 lead in this, as they have done in the cocao farming. 



G. WALDAU. 

 December, 1904. 



THE TROUBLE WITH AFRICAN RUBBERS. 



TO THE Editor of The India Rubiser World : I noticed 

 in the October i issue of The India Rubber World a 

 letter from Mr. A. D. Thornton, of the Canadian Rubber Co. 

 upon the subject of the deterioration of African rubbers ; I also 

 notice another letter in the December i issue from the same 

 gentleman, and upon careful consideration I feel that it might 

 be of some interest to the trade to give my own views upon this 

 matter. 



I cannot agree with all that Mr. Thornton says about the de- 

 terioration or African rubbers, because it has been my observa- 

 tion and experience that these rubbers do not of necessity de- 

 teriorate because of improper handling in their preparation, be- 

 cause I have noticed this in all of the Upper Congo rubbers, 

 such as Ikeleniba, " tresses," and Aruwimi, and I find that they 

 become sticky and have the appearance of being heated on ex- 

 posure to heat and light, and I have, therefore, arrived at the 

 conclusion that this was caused by the presence of resins in 

 the rubber. I have proved this to be true, at least to my own 

 satisfaction, and I think I can demonstrate it to any one inter- 

 ested that this was the case. 



Of course, every one connected with the rubber trade knows 

 that African rubbers do contain a much larger percentage of 

 resins than the South American rubbers, and it is, I believe, also 

 a well known fact that rubbers which contain a large percentage 

 of resins must be handled in a ditlerent manner from those that 

 do not contain so much ; and this is the reason, I believe, that 

 Mr. Thornton has had the trouble which he has experienced 

 with African rubbers. 



It has been my invariable custom to treat rubbers which show 

 that they contain an excessive amount of resins in an entirely 

 different manner than those that do not contain so much resin, 

 and I have never experienced any difficulty with them as yet. 

 To the subject of resin and resinous matters in rubbers I have 

 given a good deal of thought, and I have arrived at the conclu- 

 sion that this is what gives our rubber manufacturers much of 

 the difficulty which they experience in the factory with their 

 formulas, and this also has forced me to the conclusion that 

 there is no hard and fixed rule for handling rubbers. I have 



found this trouble in the case of South American rubbers, but 

 not to as great an extent as will be found in the Africans. I 

 have also arrived at the conclusion that this resin is the cause of 

 deterioration of rubber goods to a large extent after they have 

 been vulcanized, and this can only be overcome by rubber man- 

 ufacturers treating each of the various kinds of rubber as an in- 

 dividual lot, and not treating the various lots collectively. 



If this information is of any value to the trade, they are wel- 

 come to have it, because I believe in being broad minded enough 

 to be willing to " help the other fellow " with his troubles, and 

 I believe that if this policy was carried out to a greater extent 

 in the trade, we would all get better results and profit by each 

 others' experiences. wilmer dunbar, 



Factory Manager Pennsylvania Rubber Co. 

 Jeanncite, Pennsylvania, December 7, 1904. 



A CONGO RUBBER AND MINING COMPANY. 



THE report of the Cie. du Katanga for the fiscal year 1903- 

 04, while showing that their trading is still confined to 

 Caoutchouc and ivory, indicates that active work has been done 

 in the study of the mineral resources of its concession, and plan- 

 ning improved means of transportation. If the territory — in the 

 southwest of the Congo Free State — should prove as rich in 

 gold, copper, and tin as is now supposed, an important source 

 of wealth will exist after the rubber has become exhausted. An 

 attempt is being made, however, to provide for a continued 

 supply of rubber by forming plantations. The profits of the 

 company were smaller than in some former years ; the output 

 of rubber was only 85,852 kilograms, with 3949 kilos of ivory. 

 But, the report says [November 16, 1904], "it is notable that 

 the quality of the exported rubber is far superior to that of the 

 product previously gathered. Katanga rubber is at present 

 quoted at from 10 to 10.60 francs per kilogram — prices which 

 rival those asked for the best grades of rubber gathered in the 

 Congo territory." Reference is made to continued " difficult- 

 ies raised by some of the native chiefs," the pacification of 

 which has occupied the attention of the company since its for- 

 mation in 1891. One feature of the report is as follows : 



Plantations. — In the Lomami section, during the past six months, 

 more than 400,000 seeds of rubber Hants have been planted in the nurs- 

 eries, while 812,000 slips have been set out. The section at present 

 possesses 268,300 small plants, and there are 932,000 saplings on its 

 plantations. The other sections, which are only slightly wooded, are 

 likewise commencing to give their attention to the planting of Hants. 

 Nearly a million seeds of the red rubber liant of the Kasai district 

 have been introduced into these sections. An agriculturist, having been 

 sent on a special mission, visits the different posts and attends to every- 

 thing pertaining to the plantations. Besides these plantations, each 

 post has a vegetable garden, and in the mining regions large plantations 

 are being laid out for the purpose of supplying the force occupied in 

 working the mines. 



Fred E. Os(;ood and Franklin F. Bradley (No. 706,590) pro- 

 duce a resilient rubber tire, light in weight and that will not be 

 injured by punctures, by filling it with a sponge like core. 

 The process of manufacture consists in enclosing within an 

 outer covering a core of less bulk than the space within the 

 covering, and composed of a mixture of an expansible ma- 

 terial and a chemical capable of generating gas when heated, 

 and heating said mixture to generate a gas and permanently 

 expand the core to completely fill the space within the outer 

 covering. Hitherto tires have been made in which a core of 

 sponge rubber has been surrounded by a rubber tube. By this 

 method the rubber sponge and the tire proper are made in one 

 operation. 



