Man Using ENIAC Device

(Original Caption) Before starting a problem on the ENIAC, the basic equations must be set up as illustrated in a particular case. These equations are then analyzed for mounting on the ENIAC and thereafter, the results are turned out. The specific equations above refer to the motion, and for the air, as a sharply pointed projectile moves through it. These equations must be solved many times starting with certain boundary conditions at the shock wave ahead of the shell, and working backwards to conditions of the surface of the shell. It is estimated that an elementary investigation in this manner of the optimum shape of the shell would require 250 solutions each, of which would involve 90,000 multiplications and many more additions and subtractions.