We have been fortunate in successfully reproducing, on a strip of motion-picture film, electrocardiograms which really move when projected on a screen. The effect is most striking, bringing exclamations of surprise from men who have worked with electrocardiograms for years. Seeing the graph wriggle across the screen in the exact manner in which it was originally recorded (slowed, however, to a speed which the eye can easily follow), stopping obligingly at any place for explanation by the lecturer, gives one an entirely new and better conception of the electrocardiograph.
We developed this technic while casting about for a method of showing 40 feet of heart graph which Dr. Ronald Hamilton of the Guthrie Clinic staff had obtained. This graph showed the heart action of a man during an attack of angina pectoris, the quieting down of the attack, an interval, and the onset and course of a more severe and