Front view of the heart and great vessels. The pulmonary artery has been cut short close to its origin. Labels: 1, right ventricle; 2, left ventricle; 3, root of the pulmonary artery; 4, 4', arch of the aorta; 4'', the descending thoracic aorta; 5, part of the right auricle; 6, part of the left auricle; 7, 7', innominate veins joining to form the vena cava superior; 8, inferior vena cava; 9, one of the large hepatic veins; X, placed in the right auriculo-ventricular groove, points to the right or posterior coronary artery; X, X, placed in the anterior interventricular groove, indicate the left or anterior coronary artery.
Martin, H. Newell The Human Body: A Text-book of Anatomy, Physiology and Hygiene (New York: Henry Holt and Company, 1900) 167
Courtesy the private collection of Roy Winkelman