200 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1940 



we have no record of the first employment of chemists in the rubber 

 industry or why they were employed, the conventional guess would 

 be that it was in connection with the application of analytical methods 

 either to raw materials or to the finished products, including com- 

 petitors' products. An interesting side light is furnished in a 

 note by Weber (20) in 1903 entitled "The Importance of Chemistry 

 in the Kubber Industry." Weber says: 



Slowly but surely are silenced those once so numerous voices which assured 

 us positively a few years ago that the efforts of the chemists to solve the 

 chemical side of rubber manufacturing are commendable, but fail of accomplish- 

 ment, and in any case would be superfluous. The possibility of a secondary 

 usefulness of chemistry in carrying out analyses of raw materials and occasion- 

 ally of a sample of rubber, however, was admitted, with the emphatic statement 

 that herewith the importance of chemical methods had reached an end as far 

 as rubber was concerned. The only "catch" in these statements, well meant 

 without doubt, was that they were made by nonchemists. I recall quite 

 similar lamentations (Jeremiade) which greeted the arrival of chemistry in 

 the leather and paper manufacture, and also that even in the iron and steel 

 industry the chemist had been looked upon for a long time as a kind of 

 idealistically inclined spendthrift, and that it took the chemists a long time 

 to attain their present importance. 



In 1892 Henriques (6) published articles on the analysis of rubber. 



In 1890 C. O. Weber started his career in the rubber industry. 

 Weber had studied under Bunsen at Heidelberg and later at the 

 universities of Zurich and Freiburg. He had previously been inter- 

 ested in coal tar and dyestuffs. When Weber entered the industry, 

 little or nothing was known of the chemistry of rubber manufacture. 

 The phenomenon of vulcanization, of which the industry had made 

 such enormous use for over 50 years, had received practically no 

 attention even from the empirical point of view. Rubber manufac- 

 turers were still arguing as to what was meant by "perfect cure." 

 Little or nothing was known regarding the relation of time and 

 temperature to the degree of vulcanization. Although it was recog- 

 nized that sulfur did something important to the rubber, until 

 Weber's time there was no recognition of any quantitative relation. 



Weber investigated the relation between the time and temperature 

 at which rubber was vulcanized, and the amount of combined sulfur 

 in the resulting product. The percentage of combined sulfur based 

 on the rubber, he called the "degree" or "coefficient of vulcanization." 

 Thus for the first time a clear conception of the quantitative nature 

 of the process and a practical method of measuring it were available. 

 Although this method has its faults, it has been of enormous use to 

 the rubber industry in controlling and developing new products, and 

 is in general use at the present time. 



From this time on there was a rapidly increasing interest on the 

 part of the rubber industry in the application of scientific information 



