OPTICAL GLASS FOR WAR NEEDS 109 



glass and constructing new furnaces designed to give better 

 results. They were encouraged in their work by the Eastman 

 Kodak Company, which placed large orders for suitable glass 

 on a basis which took into consideration a share in the expense 

 of development. 



In June, 1915, Keuffel and Esser, finding their supply of 

 glass running low, gave permission to their glass moulder to 

 undertake optical glass making, and, _strange to say, this 

 moulder was the same Mr. Feil who had earlier been connected 

 with the Macbeth-Evans Glass Company. He made some use- 

 ful glass in Hoboken, but by November, 1915, had decided to 

 take up other work and at that time C W. Keuffel undertook 

 the task along scientific lines. Mr. Keuffel, unaided in his 

 researches, made such progress that by January, 1916, he was 

 able to produce at least one pot of boro-silicate crown from 

 which more than 200 pounds of usable glass was secured. 

 During the following months he was able to make much of the 

 glass required in that plant. 



During the summer of 1916 the Spencer Lens Company 

 built a glass furnace in their plant at Buffalo, and with the help 

 of a general glass-maker, started to work. The furnace was 

 found to be unsuited to the work and it was soon seen that 

 other arrangements would have to be made. Consequently, a 

 small plant was built in Hamburg, New York, a suburb of 

 Buffalo, in the spring of 1917, and this was later greatly en- 

 larged. When the United States entered the war, the Macbeth- 

 Evans offered their services to a department of the Government 

 and were about to enter into a contract when it was learned 

 that two ^ other departments of the Government had already 

 made arrangements for optical glass and there seemed to be no 

 further need of their services. The National Optical Glass 

 Company, a subsidiary of the Hazel-Atlas Company, of Wash- 

 ington, Pa., and the Carr-Lowrey Glass Company, of Baltimore, 

 also made some glass, but details of their achievements are 

 lacking. 



It should be emphasized that optical glass is not just glass. 



