A look at the new field of ballistocardiography. Host Dr. Patterson Hume of the University of Toronto explains the principals behind ballistocardiography. Donald Crowdis of the Nova Scotia Science Museum explains the functioning of the human heart with the aid of a model. Dr. Wilhelm Josenhans of the Department of Physiology at Dalhousie University explains his research and experimental apparatus to measure the ballistics of the flow of blood in the body. Also he explains his mechanical model of the heart pumping system and discusses some of the uses of his research.