

PRINTING APRONS. « 85 



manufacture of belts, upon which the dough is cut by the ma- 

 chines which are used for the manufacture of biscuits and 

 crackers. See plate , fig. 



This was invented by another, and tried with the native gum, 

 previous to the discovery of the vulcanizing process. 



PRINTING APRONS. 



This is an endless belt or apron, made of gum-elastic felt or 

 vegetable leather ; they are used in printing calicos and other 

 stuffs, instead of the woolen felt blankets, which have formerly 

 been used, and are objectionable on account of their expensive- 

 ness and want of durability. It is obvious that the properties 

 and texture of this fabric are such as to remedy this defect, in 

 this extensive department of industry. 



MATCH DIES. 



Gum-elastic compound has been found exceedingly useful for 

 match dies, instead of lead and copper, for striking up impres- 

 sions in paper, sheet metal, and other materials. 



WINDMILL SAILS. 



The advantages that may be derived from the use of India 

 rubber fabrics instead of common canvas for windmill sails, are 

 very obvious. They are made from plated canvas and the 

 corded fibrous fabrics. 



