8 Guayule. 



Compania Explotadora de Caucho Mexicano, from which factory rubber 

 was put on the market for the first time in 1905. In 1902, also, certain 

 American capitalists financed an . expensive but eventually successful 

 series of experiments which led to the successful extraction of the crude 

 rubber by a mechanical process (devised by Mr. Wm. A. Lawrence), and 

 two years later, in 1904, the first lot of rubber thus prepared was taken 

 by the Manhattan Rubber Company. On December 25, 1904, 50 pounds 

 of crude rubber, extracted by means of the now successfully adapted 

 pebble-mill, were shipped to the United States, over half of the amount 

 being purchased by the Manhattan Rubber Company. Then followed 

 the building of a large factory at Torreon by the Continental- Mexican 

 Rubber Company (plate 3, plate 4, fig. A), in which the results of the 

 earlier experiments were used. This event marked the beginning of 

 commercial success in the extraction of rubber from the guayule shrub 

 by the mechanical method, which has superseded all others, and it 

 should be said that this phase in the development of the industry is 

 almost entirely due to American initiative and ingenuity. 



From 1905 on a large advance in the outlay of capital followed, and 

 extracting plants of various sizes were established in San Luis Potosi, 

 Saltillo, Monterey, and Gomez Palacio, as well as at Torreon and Jimulco. 



Manufacturing enterprise has lately brought the guayule industry 

 into Texas. On September i, 1909, a factory 1 at Marathon, Texas, in 

 the heart of the guayule area of that State, began operations under 

 the Texas Rubber Company. But it should be added that the manu- 

 facture of guayule rubber had already to some extent been carried on 

 in the United States and abroad. The extent of this phase of the indus- 

 try is indicated in the total exportation of crude shrub from Mexico, 

 the statistics for which are given on p. n. 2 



At the present writing, according to Mr. Henry C. Pearson, 3 the out- 

 lay of American capital alone in Mexico amounts to $30,000,000. 



METHODS OF EXTRACTION. 



A brief statement of the principal features in the methods of extrac- 

 tion of rubber from guayule will be of interest here, especially as they 

 differ widely from nearly all hitherto-used methods of preparing crude 

 rubber from latex plants. 4 It must be understood that the rationale of 

 the processes lies in the fact that the rubber exists as such in the cells of 

 the plant, and will not escape by bleeding. 



The material must, then, either be dissolved out, after preliminary 

 grinding, by suitable chemical agents, or must be agglomerated mechan- 

 ically, either with or without the assistance of a substance (caustic soda) 

 which will attack the cell wall. The chemical method is used successfully, 

 it is understood, at Akron, Ohio, where an excellent brand of guayule 



1 Previously built and operated for a short time by the Big Bend Rubber Co. 



2 We now read that the Japanese have entered the market, and are buying 

 shrub (Dec., 1909). 



3 India Rubber World, 40 : 383, August i, 1909. 



* African "grass-rubber," however, is obtained in a crude way, but purely 

 mechanically, from species of Landolphia (Jumelle, 1903). 



