NEW SOLARIZATION PROCESS. 73 



general effects, since 1837.. and was first made known to the 

 writer by N. Hayward ; but as to its practical utility, it is not 

 even now publicly known. It was practiced to a very limited 

 extent by the writer and one or two of his licensees, previous 

 to the discovery of the vulcanizing process ; but the art being 

 then imperfectly known, was impracticable. The odor of the 

 sulphur, in the quantity in which it was then used in the 

 fabrics, was so strong as not to be endurable, and the practice 

 of solarizing has been abandoned for many years past, except- 

 ing where it has been used for drying off the tackiness of goods 

 that were vulcanized. This practice of some manufactories, 

 especially that of the Union India Rubber Company, in the 

 manufacture of garments, is one among other proofs that solar- 

 ization, to the depth to which it extends, is the most complete 

 vulcanization ; but this effect of the process does not extend to 

 any considerable depth, or so as to cure gum of the thickness 

 with which the fabrics were formerly coated. The claim to 

 the new use of solarization, and the rendering of this process 

 practically useful, by the writer, is founded in his discovery 

 that a minute portion of precipitated sulphur — in quantity as 

 small as one ounce to twenty pounds of caoutchouc — was ade- 

 quate for the desired result ; and also in his invention of the 

 "plated" fabrics, by which an extremely thin coat of caout- 

 chouc and its compounds is made to answer a better purpose 

 in all respects than the large quantity formerly used, whereby, 

 on account of the thinness of the "plating" of the fabrics, so- 

 larization may be substituted in these fabrics instead of vulcan- 

 ization. This claim of the writer to the new and improved 

 use of this process is made with the greater force and propri- 

 ety, for the reason, that up to the time of writing this article, 

 the facts here stated, as to the effects and utility of the process, 

 are generally doubted by those best acquainted with the caout- 

 chouc manufacture. After so great notoriety of the art of 

 vulcanization, wherever he now ventures to advocate his 

 opinions, it is considered little less than heresy for the discov- 

 erer of that process to treat of any other as important, and 



