THE 



POPULAR SCIENCE 

 MONTHLY. 



FEBRUARY, 1893. 

 THE GLASS INDUSTRY. 



By Pkof. C. HANFORD HENDERSON. 



THE DEVELOPMENT OF AMERICAN INDUSTRIES SINCE 

 COLUMBUS, XVII. 



ALONG the eastern base of the Rocky Mountains there is 

 found a hard, dark mineral known as obsidian, or volcanic 

 glass. It is a variety of feldspar. In the chemical sense, it is a 

 true glass, since it is a silicate of at least two metals, aluminium 

 and potassium. Physically, it half deserves the name. Though too 

 dark to be transparent, it is at least translucent ; and in its luster, 

 hardness, and glassy fracture it is quite comparable to the prod- 

 ucts of industrial glass-houses. Travelers in New Mexico are 

 offered bits of this volcanic glass by the Pueblo Indians who con- 

 gregate at Wallace and other dining stations along the railroad. 



The manufacture of glass in America seems, then, to have been 

 first set up by Nature, and may easily claim priority to all our 

 other industries. It was one of the native products used in the 

 early receptions given to the invading white man ; but lest the 

 spirit of the hospitality be misunderstood, it should be added that 

 it was served in the form of swiftly flying arrowheads. When 

 Columbus came to this country the glass industry was limited to 

 a rude fashioning of the material supplied by Nature. It had 

 been melted in fires burned out long centuries before. 



In the Europe of 1492, the operations of glass-making were still 

 very crude and inadequate. It was a rare thing to have glazed 

 windows, even in castle and palace. For many years the luxury 

 was limited to the churches, and there it was an article of decora- 

 tion rather than of utility. In domestic service, the supply of 



TOL. XLII. 29 



