124 



THE INDIA RUBBER WORLD 



[January i, 1909. 



A RUBBER TESTING COMMITTEE. 



CO imicli interest has developed in Europe regarding the 

 '>-' standardizing of methods for rubher testing, both physi- 

 cal and chcniical. that it has resulted in the formation of an Inter- 

 national Committee, of which the following is a partial list. The 

 list of names for all covmtries except the United States is, for 

 the present, complete, but the full American committee will be 

 completed later. 



liNGLAND. 



Dr. David Spence, University College, liristol. 



Dr. Joseph ToRREy, .\nalytical chemist, Liverpool. 



Mr. Herbert Wright, a. r. c. s., f. l. s., Kditor of The India-Rubber 

 Journal, London, Secretary. 



Dr. Philip Schidrowitz, f. c. s., Qiancery Lane, London. 

 FR.-\NCE. 



M. Pierre Breuil, Engineer; editor Le Caoiilchonc ct la Cutta-Percha, 

 49 Rue des \'inaigriers, Paris, Secretary. 



M. Victor Henry, Professor a la Sorbonne, Paris. 



M. Bertrand, Professor a I'Institut Pasteur, Paris. 

 GER1I.\NY. 



Professor Dr. O. Warburg, Editor Dcr Tropcn{^1lan::cr. 



Dr. F. Frank, Berlin. 



Dr. R. Weil. Continental Caoutchouc und Guttapiercha Cie., Hanover. 



Dr. F. Kl'hlemann. Teaterstrasse, Hanover. 



Dr. W. Thiel. Alsterdamm z, Hamburg. 



AUSTRIA, 



Dr. Herbst. Secretary. 



UNITED STATES. 

 Mr. H. C. l*E.\RSoN, Editor of The India Rubber World, No. 395 

 Broadway, New York, Secretary. 



CEYLON. 



Mr. M. Kelwav Bamber, Government analytical chemist, Colombo, 

 Secretary. 



HOLLAND. 



Professor Dr. S. Hoogewerff Wassenaar. Delft. 



Professor Dr. G. Van Iterson, Delft. 



Dr. M. Greshoff, Director of the Colonial Museum, Haarlem. 



M. Merens, Rubber manufacturer, Haarlem. 



Mr. A. H. Berkiiout, Wageiiingen (late conservator of forests in Java), 

 General Secretary. 



Dr. Tromp de Haas, Buitenzorg, Java. 



EXTRACTIONS OF CRUDE RUBBER. 



"T^O THE Editor of The India Rubbek World: We all have 

 ■*• used resin, ordinary pine resin and other more expensive 

 ones, harder and softer ones, in rubber mixings for various pur- 

 poses. Being a very near relation to rubber, resins have a 

 greater and are a greater affinity to the rubber molecule than for 

 instance zinc oxide or any other mineral oxides, chalk, oils, etc. 



Ergo, used and applied in moderation, resins are useful com- 

 pounding ingredients. The aim of many processes has been to 

 extract resins. Extractions mean the use of solvents and there is 

 not a process using solvents which has not proved disastrous. 

 Solvents can only be recovered partly. They often affect the 

 quality of the extracted gum. But why extract something which 

 may be made useful by ordinary methods? For instance, let us 

 take the percentage of rubber in Pontianak as 15 per cent., 

 resinous contents 85 per cent. Now the rubber required in a 

 mixing shall have a tensile strength of a rubber containing 15 per 

 cent, of resins only. 



Make a combination of crude rubbers giving the required aver- 

 age percentage of resins. All one needs to know is the exact 

 percentage of resin in each rubber : the rest is simple. Such a 

 combination would of course contain a proportionate amount of 

 Pontianak in its native state and other rubbers to match. 



I have come to the conclusion that one of the most important 

 factors in working qualities of a mixing is the proper blending 

 of crude rubbers, rot only because one obtains a fixed percentage 

 of resins on a reliable basis, but because there is a distinct 

 reaction of one resinous compound upon another, causing prac- 

 tical results of value. 



There is of course the ideal condition of affairs still to be 

 worked upon — that is, resinous compounds being so closely re- 



lated to rubber may some day lose their identity and become more 

 like their twin brother by a process which would result in imi- 

 tating nature to some extent. She does it to-day successfully. 



How far scientific research work has enabled us to get is repre- 

 sented by some of the new rubber products on the market. 



New York, December 8, 1Q08. ^- ^- 



RUBBERED FABRICS FOR BALLOONS. 



■"PO THE Editor of the India Rubber World: Referring to 

 ■^ your inquiry, I have no printed matter at hand relating to 

 the rubber-coating of balloons, but if you will refer to "Apple- 

 ton's Encyclopedia" you will find, under head of Modern Balloon- 

 ing, an article, written by myself, where my method of coating 

 with rubber is mentioned. 



For certain reasons this sort of coating is exceedingly valuable, 

 particularly where haste is required, or when two or more lay- 

 ers of cloth have to be cemented together. But rubber cannot 

 compete with the best oil-varnished fabrics in retaining imper- 

 meability — the portions most exposed to the sun quickly drying 

 out, hardening, and becoming porous. There is room for im- 

 provement, of course, and the demand for a double silk fabric 

 for dirigible balloons like Baldwin's recently made for the United 

 States government may suggest a combination coating rubber 

 within and varnish without. A black varnish over the top of a 

 dirigible balloon would seem to be a protection to the rubber in 

 the most exposed portion, but the varnish must be of a kind that 

 will not affect the rubber. 



I would not advise manufacturers to anticipate any considerable 

 demand of rubber goods for balloon purposes. The orders must 

 necessarily be few and far between, but it might be very con- 

 venient to know where the goods could be procured at the shortest 

 notice. Yours truly, samuel a. king. 



No. 5134 Ridge avenue, Philadelphia. 



RUBBER-ASPHALT ROADWAY IN FRANCE. 



A RECENT report by the United States consul-general at 

 Marseilles relates to rubber-asphalt roadways, with which 

 experiments have been made for six years past in Marseilles, 

 Paris, Lyons and other French cities, and which as far as can 

 be ascertained have given good results. From Mr. Skinner's 

 report it would appear that the areas thus far paved under the 

 new system are devoted to pedestrian traffic exclusively, "but 

 from the character of the men interested in the company and the 

 increasing importance of the work undertaken, rubber-asphalt 

 paving must be regarded very seriously as a substitute for the 

 more usual form of asphalt paving." The rubber-asphalt paving 

 thus far has been confined to the work of a single company, 

 operating a patented process, the details of which are not given 

 fully. It is stated, however, that "the asphalt reduced to a fine 

 powder is in the presence of rubber swelled and softened by 

 a solvent. The material thus obtained is a brown powder darker 

 than the original asphalt, and it suffices to compress it in order 

 that it shall set and harden rapidly." This pavement is laid 

 upon a foundation of first-class concrete, to a thickness of 1.37 

 to 1.5- inches. After the application to it of a rammer the 

 surface may be opened immediately to travel. 



In a recent issue of Daily Consular and Trade Rcj^orts (No. 

 3ii7) the United States consul at Port Elizabeth, Cape Colony, 

 refers to some "root rubber" plants which he regards as new and 

 of which he sends rough sketches. It happens that these plants 

 have been described at some length in The India Rubber World: 

 "Ekanda" (Rafhionacmc utiUs) in our issue of July i, 1907 — 

 page 300 and Atractylis gununifcra in Afarch i, igo8 — page 177. 

 The consular report intimates that ;\lr. O. W. Barrett, of the 

 United States department of agriculture, is now making some 

 investigations of rubber plants in Portuguese East Africa. 



