Page:The Harveian oration - delivered at the Royal College of Physicians June 24, 1882 - by George Johnson (IA b21517046).pdf/59



Harvey demonstrated the passage of blood through the lungs and the impermeability of the septum cordis by an experiment which he thus describes in one of his letters to Schlegel:-

'Having tied the pulmonary artery, the pulmonary veins, and the aorta in the body of a man who had been hanged, and then opened the left ventricle of the heart, we passed a tube through the vena cava into the right ventricle of the heart, and having at the same time attached an ox's bladder to the tube we filled it nearly full of warm water, and forcibly injected the fluid into the heart, so that a greater part of a pound of fluid was injected into the right auricle and ventricle. The result was that the right ventricle and auricle were enormously distended, but not a drop of water or of blood made its escape through the orifice in the left ventricle. The ligatures having been undone, the same tube was passed into the pulmonary artery, and a tight ligature having been put round it to prevent any reflux into the right ventricle, the water in the bladder was now pushed towards the lungs, upon which a torrent of the