p. 109 | PHOTOGRAPHING BULLETS

International Tract and Missionary Society · Oakland, California · Feb 18, 1889

FromThe Signs of the Times, Vol. 15, No. 7

PHOTOGRAPHING BULLETS.

THE interesting process of photographing rifle bullets in motion, by means of the electric light, presents some remarkable phenomena, judging from the experiments made by Mach, the Austrian chemist. In this operation his plan is to illume the bullet by letting it break an electric current formed; but the velocity of the bullet must exceed that of sound, in order that the condition of the air before and behind the projectile can be shown. After various experiments he succeeded in his efforts to photograph projectiles fired by Wernal and Jurde guns, having respectively an initial velocity of 438 and 520 meters per second. The photographs obtained in this manner showed the air formation in front of the bullet having the form of an hyperbola, while behind it almost a vacuum was formed, in which, when the initial velocity was very great, there were some curious spiral motions. From the description given, there appeared from these photographs to be a great similarity between the motion of a body through the water and that of a projectile through the air.—Pittsburg Dispatch.