Harvey

The Evolution of Modern Medicine
by William Osler

(Page 12 of 16)

LET us return to Padua about the year 1600. Vesalius, who made the school the most famous anatomical centre in Europe, was succeeded by Fallopius, one of the best-known names in anatomy, at whose death an unsuccessful attempt was made to get Vesalius back. He was succeeded in 1565 by a remarkable man, Fabricius (who usually bears the added name of Aquapendente, from the town of his birth), a worthy follower of Vesalius.

In 1594, in the thirtieth year of his professoriate, he built at his own expense a new anatomical amphitheatre, which still exists in the university buildings. It is a small, high-pitched room with six standing-rows for auditors rising abruptly one above the other. The arena is not much more than large enough for the dissecting table which, by a lift, could be brought up from a preparing room below. The study of anatomy at Padua must have declined since the days of Vesalius if this tiny amphitheatre held all its students; none the less, it is probably the oldest existing anatomical lecture room, and for us it has a very special significance.

Early in his anatomical studies Fabricius had demonstrated the valves in the veins. I show you here two figures, the first, as far as I know, in which these structures are depicted. It does not concern us who first discovered them; they had doubtless been seen before, but Fabricius first recognized them as general structures in the venous system, and he called them little doors.

The quadrangle of the university building at Padua is surrounded by beautiful arcades, the walls and ceilings of which are everywhere covered with the stemmata, or shields, of former students, many of them brilliantly painted. Standing in the arcade on the side of the "quad" opposite the entrance, if one looks on the ceiling immediately above the capital of the second column to the left there is seen the stemma which appears as tailpiece to this chapter, put up by a young Englishman, William Harvey, who had been a student at Padua for four years. He belonged to the "Natio Anglica," of which he was Conciliarius, and took his degree in 1602.

Doubtless he had repeatedly seen Fabricius demonstrate the valves of the veins, and he may indeed, as a senior student, have helped in making the very dissections from which the drawings were taken for Fabricius' work, "De Venarum Osteolis," 1603. If one may judge from the character of the teacher's work the sort of instruction the student receives, Harvey must have had splendid training in anatomy. While he was at Padua, the great work of Fabricius, "De Visione, Voce et Auditu" was published, then the "Tractatus de Oculo Visusque Organo", and in the last year of his residence Fabricius must have been busy with his studies on the valves of the veins and with his embryology, which appeared in 1604. Late in life, Harvey told Boyle that it was the position of the valves of the veins that induced him to think of a circulation.

Harvey returned to England trained by the best anatomist of his day. In London, he became attached to the College of Physicans, and taking his degree at Cambridge, he began the practice of medicine. He was elected a fellow of the college in 1607 and physician to St. Bartholomew's Hospital in 1609. In 1615 he was appointed Lumleian lecturer to the College of Physicians, and his duties were to hold certain "public anatomies," as they were called, or lectures. We know little or nothing of what Harvey had been doing other than his routine work in the care of the patients at St. Bartholomew's. It was not until April, 1616, that his lectures began. Chance has preserved to us the notes of this first course; the MS. is now in the British Museum and was published in facsimile by the college in 1886.

The illustration will give one an idea of the extraordinarily crabbed hand in which the notes are written, but it is worth while to see the original, for here is the first occasion upon which is laid down in clear and unequivocal words that the blood CIRCULATES. The lecture gave evidence of a skilled anatomist, well versed in the literature from Aristotle to Fabricius. In the MS. of the thorax, or, as he calls it, the "parlor" lecture, there are about a hundred references to some twenty authors.

The remarkable thing is that although those lectures were repeated year by year, we have no evidence that they made any impression upon Harvey's contemporaries, so far, at least, as to excite discussions that led to publication. It was not until twelve years later, 1628, that Harvey published in Frankfurt a small quarto volume of seventy-four pages, "De Motu Cordis." In comparison with the sumptuous "Fabrica" of Vesalius this is a trifling booklet; but if not its equal in bulk or typographical beauty (it is in fact very poorly printed), it is its counterpart in physiology, and did for that science what Vesalius had done for anatomy, though not in the same way.

The experimental spirit was abroad in the land, and as a student at Padua, Harvey must have had many opportunities of learning the technique of vivisection; but no one before his day had attempted an elaborate piece of experimental work deliberately planned to solve a problem relating to the most important single function of the body. Herein lies the special merit of his work, from every page of which there breathes the modern spirit. To him, as to Vesalius before him, the current views of the movements of the blood were unsatisfactory, more particularly the movements of the heart and arteries, which were regarded as an active expansion by which they were filled with blood, like bellows with air. The question of the transmission of blood through the thick septum and the transference of air and blood from the lungs to the heart were secrets which he was desirous of searching out by means of experiment.

One or two special points in the work may be referred to as illustrating his method. He undertook first the movements of the heart, a task so truly arduous and so full of difficulties that he was almost tempted to think with Fracastorius that "the movement of the heart was only to be comprehended by God." But after many difficulties he made the following statements: first, that the heart is erected and raises itself up into an apex, and at this time strikes against the breast and the pulse is felt externally; secondly, that it is contracted every-way, but more so at the sides; and thirdly, that grasped in the hand it was felt to become harder at the time of its motion; from all of which actions Harvey drew the very natural conclusion that the activity of the heart consisted in a contraction of its fibres by which it expelled the blood from the ventricles. These were the first four fundamental facts which really opened the way for the discovery of the circulation, as it did away with the belief that the heart in its motion attracts blood into the ventricles, stating on the contrary that by its contraction it expelled the blood and only received it during its period of repose or relaxation.

Then he proceeded to study the action of the arteries and showed that their period of diastole, or expansion, corresponded with the systole, or contraction, of the heart, and that the arterial pulse follows the force, frequency and rhythm of the ventricle and is, in fact, dependent upon it. Here was another new fact: that the pulsation in the arteries was nothing else than the impulse of the blood within them. Chapter IV, in which he describes the movements of the auricles and ventricles, is a model of accurate description, to which little has since been added. It is interesting to note that he mentions what is probably auricular fibrillation. He says: "After the heart had ceased pulsating an undulation or palpitation remained in the blood itself which was contained in the right auricle, this being observed so long as it was imbued with heat and spirit." He recognized too the importance of the auricles as the first to move and the last to die. The accuracy and vividness of Harvey's description of the motion of the heart have been appreciated by generations of physiologists.

About the Author

William Osler (1849 - 1919) was a Canadian physician. He has been called one of the greatest icons of modern medicine and the Father of Modern Medicine (which is what he himself considered Avicenna to be).