320 Proceedings of Indiana Academy of Science. 
SOME CONTRIBUTIONS OF PHYSICAL SCIENCE TO MILITARY 
EFFICIENCY. 
C. M. SmiruH, Purdue University. 
The technical and popular press has of late been offering much valu- 
able material which shows the contributions of the physicist and the 
research laboratory to war problems. Moreover before these Proceed- 
ings are printed and circulated it is certain that much more information 
along the same line will be released. It is not the purpose of this paper 
to give a complete catalog of the achievements of physical science in the 
war, nor to set forth in detail the devices which have been developed and 
applied. It is, however, my purpose to sketch briefly some of the general 
lines along which the physicist gave aid to the military forces, and to 
point out some of the valuable results which have followed from the 
large activities and generous appropriations which were called out by 
the pressure of war conditions. 
It will undoubtedly appear that instances are rare where war-inspired 
research has resulted in the discovery of any distinctly new principle or 
law. The lay public, keenly alert for some wonderful invention or dis- 
covery, which should overwhelm the opponent as by a great cataclysm, 
frequently voiced the question why our active scientists were not bring- 
ing forward this all-important achievement. But the hoped-for result 
did not come about. Rather the achievements of physical science in the 
war consisted in the application of already well-known principles, but 
with a refinement and a precision heretofore not realized. The careful 
consideration from the standpoint of theory of the lines and balance of 
a shell, of the form of its ends, and of the proper width and thickness 
of its copper band resulted in the addition of miles to its range and 
increased the accuracy of gunfire manyfold. Such precision studies, 
often highly theoretical in nature, growing in numbers to scores or hun- 
dreds, all contributed to an increased efficiency of the military forces, 
and their full value cannot at this time be realized. 
Studies similar to the above resulted in ovr becoming free from 
European markets in the matter of high-grade optical glass. Precision 
methods of glassworking, amounting almost to quantity production, were 
developed, and lenses and prisms large and small, and plane parallel 
plates were turned out in large numbers with an exactness heretofore 
hardly thought possible. In photography, in the great development of 
