352 GOODYEAR ON GUM-ELASTIC. 



The unsuccessful attempt by the inventor to manufacture 

 mail-bags of gum-elastic, previous to the discovery of the vul- 

 canizing process, has been noticed in the first volume of this 

 w^ork ; this was followed by another premature attempt of the 

 licensees to make them of vulcanized coated canvas. These, 

 although answering a tolerable purpose, did not give satisfaction, 

 owing to the weight of the article, and the gum peeling from the 

 canvas. This last obstacle to the use of these fabrics as a sub- 

 stitute for leather, has frequently been remarked upon, and also 

 the manner in which the difficulty is removed by the invention 

 of the fibrous fabrics, felt and vegetable leather. Since the in- 

 vention of these fabrics, specimens of mail-bags have been 

 made, which, in the judgment of those who have seen them, 

 cannot fail to answer the purpose for which they are made. 

 They are constructed of corded and barred fibrous and plated 

 fabrics, fastened in the usual way with the chain, or with jaws, 

 like the ships' letter bags. See Chapter , fig. 



HORSE MAIL-BAGS. 



Horse mail-bags are used for conveying mails on horseback, 

 in parts of the country where it is impossible or difficult to con- 

 vey them in coaches or wagons. They are, therefore, more ex- 

 posed than other mail-bags to be lost or injured by water in ford- 

 ing rivers. A gum-elastic bag of this sort has been constructed 

 of gum-elastic fabrics, in the form of the common portmanteau ; 

 and when the mouth is closed with a water and air-proof fas- 

 tening, as represented plate , fig. , they may be made to 

 answer the purposes of a life-preserver, both for the horse and 

 rider, in fording rivers. 



BOTTLES. 



Several kinds of gum-elastic and covered bottles have been 

 noticed under their respective heads, Chapters 



fe 



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