THE RUBBER INDUSTRY — GIBBONS 195 



Let us consider briefly the technical aspects of Goodyear's inven- 

 tion. What he did was to make a mixture of 25 parts of rubber, 5 

 parts of sulfur, and 7 parts of white lead, and subject this mixture 

 to heat. He found that when a piece of this mixture was heated on 

 a stove it was changed. The result was the first piece of vulcanized 

 rubber. Geer (3) ^ has given a vivid description of this event. He 

 pointed out that the only "accident" was that the stove happened to 

 be about the right temperature to produce the phenomenon of vul- 

 canization; had it been much hotter the rubber would have been 

 destroyed, and had it been much cooler no effect would have been 

 noticed. Geer also pointed out that by this apparently simple opera- 

 tion Goodyear made four discoveries: (a) Sulfur is required; (5) 

 another material, such as white lead, is important in accelerating the 

 reaction; (c) the mixture must be heated; and {d) it must be heated 

 for a definite length of time. 



Sulfur, or at least gunpowder, had been used by the Indians as a 

 dusting material to remove surface tack. Hayward had previously 

 obtained a patent on exposing mixtures of rubber and sulfur to sun- 

 light, with the object of drying the surface. White lead was a com- 

 mon pigment. Hancock and others had found that heat could be 

 used to amalgamate pieces of scrap rubber to make a homogeneous 

 mass. Before Goodyear's discovery, however, no one had combined 

 these four operations. 



The story of rubber from the discovery of vulcanization to the 

 present time cannot be told as a simple sequence of orderly, related 

 developments. For the first half of this period we have two lines 

 of independent progress. One of these is the development and ex- 

 pansion of the rubber industry; the other is the scientific study of 

 rubber. Probably for the most part the workers in one field did not 

 know what those in the other were doing. This same situation un- 

 doubtedly existed in many industries as a result of the slowness of 

 manufacturers to interest themselves in the application of scientific 

 methods to their work. 



COMMERCIAL DEVELOPMENT TO 1S90 



Shortly after the discovery of vulcanization Goodyear granted 

 a number of licenses. The first, dated April 3, 1841, was to Nathaniel 

 Hayward and related to "boots and shoes of felt or woolen cloth and 

 India rubber." Hayward later transferred this license to Leverett 

 Candee of New Haven, who together with Henry Hotchkiss and 

 Lucius Hotchkiss had formed a partnership for the manufacture 

 of rubber shoes, etc. This was the origin of L. Candee & Co., which 



' Numbers In parentheses refer to list of references at end of article. 

 280256—41 14 



