OPTICAL GLASS FOR WAR NEEDS 107 



It is true that optical glass was also being made in England 

 and France, but those countries needed all the glass they could 

 produce, and as a result, the glass sent here, although for use 

 in instruments being made for their accounts, was not always 

 wholly satisfactory. 



That very high-grade optics are essential in modern warfare 

 is at once obvious when we consider improvements in Ordnance. 

 In the days of the Revolution the combatants are said to have 

 waited until they could see the whites of the eyes of their 

 enemies before firing; in the Civil War firing was point-blank; 

 in the Spanish War 6,000 yards was the maximum graduation 

 required on the range-finder. Today the horizon is the limit 

 in the larger instruments, and much progress has already been 

 made with range-finding methods which are necessary for dis- 

 tances beyond the range of observation from the ground. 



Now what is the history of optical glass in America? The 

 oldest record states that some fair-grade optical glass was made 

 by the Macbeth-Evans Glass Company in the period between 

 1890 and 1893, during which time they had the assistance of a 

 Mr. Feil, a French glass- worker who had had experience with 

 Mantois. Both crown and flint were made but there are no 

 details as to the quantity produced, the percentage of usable 

 glass secured, nor the quality. At that time, as later, there was 

 no demand for other than European glass, the cost of develop- 

 ment would have been large, and the results quite uncertain. 

 Even if success was attained in producing usable glass, the 

 total volume of the business has never been such as to be 

 attractive, so that the work ceased. The next date is 1903, 

 when Mr. William Bausch, of the Bausch and Lomb Optical 

 Company, conducted a few small-scale experiments, but only 

 with discouraging results. The question remained dormant 

 until 1912, when Mr. Bausch resumed his work and had a 

 small, round, oil-fired furnace constructed. It was soon found, 

 however, that it was impossible to properly control this furnace 

 and in the spring of 1913 the firing was changed over to uncar- 

 buretted gas supplied by the local artificial gas company. 



