8 SCIENCE 



it could be subject, the gunner to measure the 

 resistance to the motion of the shell, to plot 

 its trajectory, determine its time of flight for 

 various ranges, set his fuse, and design his 

 sights so that his shooting may be accurate. 

 But the long range gunnery of our modern 

 ships, the high angle fire required for anti- 

 aircraft work, have each introduced new 

 difficulties, and in solving these Cambridge 

 men such as Littlewood, Hill, Richmond, 

 Herman, Gallop and Fowler have been well 

 to the fore, while for anti-aircraft work the 

 Bennett heightfinder in one of its many forms 

 is in general use in the Allied Armies. 



One striking feature has been the develop- 

 ment of methods of accurate workmanship. 

 With some few exceptions all the gauges for 

 munitions pass through the National Physical 

 Laboratory. About 400,000 have been dealt 

 with in the last eighteen or twenty months. 



