632 



SCIENCE 



[N. S. Vol. XLVII. No. 1226 



numbers every meeting in whicli arrangements 

 had been made for it. The local committee 

 on arrangements and the medical profession 

 of Chicago are to be congratulated on the re- 

 sults of this session, and the thanks and ap- 

 preciation of every Fellow of the American 

 Medical Association is due them. 



THE PRODUCTION OF OPTICAL GLASS IN THE 

 UNITED STATES 



The War Industries Board authorizes the 

 statement that before the war little effort was 

 made to produce optical glass in the United 

 States. Manufacturers of optical instruments 

 w«re able to obtain optical glass in desired 

 quantity and quality from Europe and conse- 

 quently did not feel the necessity for making 

 it themselves. In 1912, however, the Bausch 

 & Lomb Optical Co., of Eoehester, IST. T., built 

 an experimental optical-glass plant and placed 

 a practical glassmaker in charge; by 1914 this 

 company was able to produce a few types of 

 optical glass which was used in optical instru- 

 ments. 



By the end of 1914 the importation of optical 

 glass had become difficult and uncertain. 

 Other firms, as Keuffel & Esser, of Hoboken, 

 N. J., and Spencer Lens Co., Buffalo, IST. T., 

 and the Bureau of Standards of the Depart- 

 ment of Commerce, at Washington, began to 

 experiment in making optical glass. By 1917, 

 when the United States entered the war, the 

 optical glass situation had become critical. 

 The European supply was practically cut off. 

 Optical glass had to be made in this country if 

 our army and navy were to receive the fire- 

 control instruments which they needed. 



The Geophysical Laboratory of the Carnegie 

 Institution of Washington was called upon to 

 aid in the production of high-grade optical 

 glass. A party from the laboratory was sta- 

 tioned at the plant of the Bausch & Lomb 

 Optical Co. in April, 1917, and for seven 

 months all efforts of the laboratory were con- 

 centrated at this plant. At the end of 1917 

 the essential details of the manufacture had 

 been developed and glass in considerable quan- 

 tities was being produced. The efforts of the 

 laboratory were then extended to the Spencer 

 Lens Co. and to the Pittsburgh Plate Glass 



Co., Pittsburgh, Pa. During this period the 

 Bureau of Standards rendered effective aid. 



At the present time, as a result of coopera- 

 tion between the manufacturers and scientists, 

 large quantities of optical glass of the kinds 

 needed for military fire-control instruments 

 are being produced of a quality equal in prac- 

 tically every respect to the best European 

 glass. The need for a continuous and assured 

 supply of optical glass is so great that the 

 workmen trained in the details of manufac- 

 ture and subject to draft, are being withheld 

 from the draft in order that their technical 

 training may be utilized at this time. The re- 

 quired information and details of manufac- 

 ture and the skill necessary for proper produc- 

 tion have been gained at great expense and 

 under high pressure. 



THE SOURCE OF TRENCH FEVER> 



A CABLEGRAM from the commanding general 

 of the American Expeditionary Eorces to the 

 Secretary of War reports the success of a 

 trench-fever investigation, which was made 

 possible through the willingness of sixty-six 

 American soldiers to risk their lives. The mes- 

 sage contains the names and home addresses 

 of the men who submitted to inoculation. All 

 of them now are either cured or convalescent. 



These men were from field hospitals and 

 ambidance organizations, units commonly des- 

 ignated as noncombatant. They were selected 

 from a large group of volunteers as the health- 

 iest and consequently the best able to with- 

 stand a long siege of trench fever, which has 

 been one of the most baffling diseases which 

 the allied armies have encountered. The men 

 selected were sent to a hospital behind the 

 British front line in January. 



Trench fever is a disease which has been 

 common on the western front. It may have 

 existed before, but has not been either fre- 

 quent or severe enough to direct the attention 

 of the medical profession. ISTow it represents 

 one of the greatest causes of disability in the 

 allied armies. I^othing definite was known 

 about either the cause or mode of spread of 

 this disease. 



1 Publication authorized by the Secretary of 

 War. 



