Cameron Heartometer. This diagnostic device was used to measure and graph a patient's blood pressure, heart rate and well as an early attempt to measure the patients heart-beat wave similar to what a modern EKG does. ÒThe Cameron Heartometer. Invented in 1937, it was one of the first medical instruments to take measurements from visual means (lights actuated by the pulse), rather than by sound. This insured the most accurate way of measuring and permanently recording systolic and diastolic blood pressures, pulse rate, the force and character of heart action and peripheral vascular circulation throughout the extremities. The Heartometer was so successful that a separate yet affiliated company was formed for its distribution.Ó H 17 3/4" W 12 3/4" D 5 7/8". H 5 3/4 W 8" Copy and paste this link for a high-res image: https://www.dropbox.com/s/7ep8vztsz5o9dua/6482143_1.jpg?dl=0