Segment 1 The narrator introduces the film and gives a brief explanation of why this update of the 1928 and 1957 films of the same title was made. Since 1957, research has found a slightly different account of William Harvey's research leading his conclusions about the circulation of the blood, and so it was decided to make a new film. William Harvey's biography is given, including his education in England and at the University of Padua, and his career in London and as physician to Kings James I and Charles I. The contemporary opinion on the circulation of the blood based on 2nd century physician Galen's writings is set out, and an animation shows Galen's opinion that blood originated in the liver and was endowed there with 'natural spirits'. Time start: 00:00:00:00 Time end: 00:04:54:22 Length: 00:04:54:22
Segment 2 The animation of Galen's opinion continues, showing his belief that blood entered the right ventricle of the heart through the vena cava, from where some went to the lungs and some passed through minute pores to the left ventricle, where it was infused with 'inspired air'. Next, a brief history of the University of Padua is given, and film of it as it is now is shown. It excelled in anatomy teaching, and its anatomy teachers are described. The first teacher, Vesalius, could not find the pores that Galen supposed were in the heart, but did not deny their existence. The next teacher, Columbus did deny the existence of pores and also of vapours in the left ventricle, and came closest to describing the circulation of the blood. Time start: 00:04:54:22 Time end: 00:10:56:15 Length: 00:06:01:22
Segment 3 Fabricius, Harvey's own teacher, did not challenge Galen or believe Columbus' work, but did demonstrate the function of valves in the veins. Harvey's early writing shows that he believed in Columbus' findings, and Harvey performed many experiments to deduce the actions of the heart. His writing is read out over a montage of various animal hearts beating. He explains it is easier to see the motions of the heart in cold-blooded animals, or warm-blooded animals that are closer to death. Time start: 00:10:56:15 Time end: 00:16:04:05 Length: 00:05:07:19
Segment 4 Harvey analysed the action of the heart and demonstrated that blood was thrown by the contraction of the aorta into the ventricles, and by the contraction of the ventricles into the arteries. His descriptions of his experiments are read out. An experiment is recreated where the heart is cut as it contracts, forcing the blood out of the cut. An animation shows Harvey's next findings, that of the blood going from the right ventricle by the pulmonary artery into the lungs and from there by the pulmonary veins into the left aorta and left ventricle. He disproves the theory of hidden pores, and a dissected heart is shown. He also describes the function of the valves at the opening of the pulmonary artery. Time start: 00:16:04:05 Time end: 00:21:35:21 Length: 00:05:31:16
Segment 5 In 1651 he related in a letter his experiment to prove that the septum was a solid wall, and the recreation is shown. The pulmonary artery, pulmonary vein and aorta are tied shut and a cut is made in the left ventricle. A tube is passed through the vena cava into the right ventricle, and warm water pumped in. The right ventricle and aorta become full, but no water comes out of the cut in the left ventricle. Next, the ties are cut and the tube put in the pulmonary artery. When water is pumped in, it gushes out of the hole. An extract from his book 'De Motu Cordis' is read, describing how he first came to think that the blood moves around the body in a circle. He also guessed at the quantity of blood in the body, and animations show how he tried to calculate this. Time start: 00:21:35:21 Time end: 00:26:18:03 Length: 00:04:42:11
Segment 6 Harvey's next experiments showed that the arteries received blood from the veins through the heart. A dissected snake is shown, with a still-beating heart. The vena cava is compressed with forceps, and the heart begins to empty of blood as it continues to beat it out, but can draw none in. The artery above the heart is then compressed, and the heart swells as it draws in blood but none can escape. Harvey also had to prove that blood returned to the heart through the veins. He could not see the tiny capilliaries, but deduced that something like them was there. He experimented by tying a man's arm, stopping the artery. The tie is then loosened slightly and the blood moves down the artery but the veins become swollen. A dissected rat is shown, and the vein and artery cut in different places to show the direction of the flow of blood in each. Harvey once saw a fire engine in London, and its water pump and hose reminded him of the way blood shot out of a cut artery. Time start: 00:26:18:03 Time end: 00:32:24:02 Length: 00:06:05:28
Segment 7 Following on from the work of Fabricius, Harvey demonstrated the role of the valves in the veins. A dissected vein is shown, and a probe is pushed in both directions through the vein. In one direction the probe is stopped by the valve, and in the other, it passes through unhindered. Experiments with a man's arm are shown; with a finger pushing blood up and down a vein, showing the action of the valves. An animation shows Harvey's final conclusions about the circulation of the blood, and an extract of his work is read out. He states that the blood moves perpetually and that the motion and pulsation of the heart is the only cause of this. The narrator says that when Harvey died, his theory had won general acceptance and that he knew it would be far-reaching. Time start: 00:32:24:02 Time end: 00:38:30:19 Length: 00:06:06:17