30 GOODYEAR ON GUM-ELASTIC. 



this material as a binding or covering for books, consists in this, 

 that it does not crack or warp, is not injured by worms, water, 

 or oil, is not easily soiled, and is readily cleansed when soiled. 

 Beside, it admits of every style of ornament in the highest per- 

 fection. 



When finished in the style of the indelible fabrics, described 

 on page , or gilded, it admits of all the elegance of execution, 

 and possesses all the durability, that can be desired in a book 

 cover. 



Admitting that these fabrics possess the advantages for book- 

 binding that are claimed for them, another and a great recom- 

 mendation will be their cheapness and economy ; as those 

 which are designed as substitutes for morocco, calf, and Russia 

 leather, may be afforded at nearly the same price as cambrics 

 and paper, and at about the price of the cambrics now used for 

 bindina;. 



OUTLINE MAPS. 



These are printed upon the vulcanized India rubber fabrics, 

 both transparent and opaque, and also upon various articles 

 to be used for other purposes besides maps, such as piano-covers, 

 crumb-cloths, and carpets. Arrangements are being made foi 

 this manufacture, which may facilitate the method of teaching 

 from outline maps, by printing on this material maps of the 

 world, upon a scale large enough for papering the sides of an 

 ordinary sized room of a school-house, academy, or public lecture- 

 room or dwelling. The same map, when suspended at a suitable 

 distance from the wall, with lights placed behind it, may be 

 used as a transparency for teaching at night. A series of sec- 

 tional maps, printed on a scale as large as can be conveniently 

 printed upon callenders, after the manner of calico printing, are 

 cemented together and arranged upon rollers, as represented in 

 plate ii., so that they may be passed from one roll to the other. 

 With the map of the world before the pupils or audience, the 



