An Appreciation OF HARVEY AS ANATOMIST.

MAY 19, 1928. "

An Appreciation OF

HARVEY AS ANATOMIST. Prepared for

the

Harvey Tercentenary Celebration

BY SIR ARTHUR KEITH, M.D. ABERD., F.R.S., PRESIDENT, BRITISH ASSOCIATION ; CONSERVATOR OF MUSEUM AND HUNTERIAN PROFESSOR, ROYAL COLLEGE OF SURGEONS OF ENGLAND.

To understand how any given masterpiece of art has come into existence we must have access to the studies, sketches, and ideas which preceded its execution. It is also so in the case of great inventions ; it is not the finished

mechanism which interests the student of discovery, but the crude first attempts and the imperfect models of the inventor. It is also so in the world of bio-

writes in another ; " Nature ever perfect and divine in a third. " But is not the thing rather arranged as it is by the consummate providence of Nature ? ’’ is a question he puts to his reader. If Harvey thought thus he must have perceived that, in setting valves in the veins, with their catching edges directed towards the heart, either Nature had blundered or Fabricius had misread Nature’s design. his teacher inquirer makes a flaw in his teacher’s Often the young argument the point of departure for his own research, and it is probable that this was the case with Harvey. The first clue that put him on the track of his great discovery was probably his search for an explanation of those minor structures-the valves of veins. How soon he took to examining the action of valves as revealed in the distended veins of the living arm and that in life they prevented any kind of renux, we cannot say. In this, as in all other instances, he never failed to put anatomical conjecture to the test of physiological proof. Herein we see that Harvey was

logical discovery ; Harvey’s masterpiece " De Motu Cordis," is the most perfect thing in the annals of biological discovery, but it is only the com-

pleted picture

that very rare

kind of man-the perfect anatomist. Long before he left Padua it must have dawned on Harvey that all was not well witli the doctrine which the

leading

ana-

tomist of the day taught his pupils

we

have-the one which he gave to the world-after he had laboured on it for a quarter of a century. Nounfortuwhere. nately. does he tell us what set him off on his quest, nor the order of events which convinced him that he was right and all the rest of the world wrong. We may be certain, I think, that his inspiration and his first clues came to him as he learned to foruse scalpel, ceps, and probe in

concerning":th

e of the heart and of its great vessels. If

uses

" Nature had made nothing in vain," why had such

a

useless

structure as the ventricle. right "

an

apparatus of

fibres, braces, and

valves," been added to the heart? Why should there be placed within the heart and in the

pulmonary artery

and aorta contrivances which were as perfect in their mechanical action as the " clacks of WILLIAM HARVEY. the pursuit off a water bellows" r From the portrait i5elonging to the Royal Oollege of Physicians of London. If the heart was. anatomy. When Harvey was studying in Padua, his as Fabricius taught, merely a vat in which blood was master, "the celebrated Hieronymus Fabricius of concocted and vital spirits brewed, such structureswere purposeless. And why should the lung require Aquapeiiclente, a most skilful anatomist and old man," was preparing his monograph on the valves such an enormous blood-supply ? Fabricius could of the veins (published in 1603), and his pupils explain none of these things and the first duty of an havehad their attention concentrated on these anatomist is to explain. mechanical contrivances. A keen student is always I At several points of his argument Harvey makes attracted to subjects investigated by his teacher.1 statements which suggest that there was another and Fabricius taught, as was accepted by all of his day,l weightier reason which caused him to be dissatisfied that the blood in the veins flowed outwards with what Fabricius taught concerning the action of the heart to the periphery and that valves had been the heart. In Chapter V., and again in Chapter ’L, set in the walls of veins to regulate the distribution’, he states that " the grand cause of doubt and error in of blood to dependent parts. Now, we see that at this subject (the circulation of the blood) appears to every point of his final argument Harvey accepts the me to havebeen the intimate connexion between dictum of Galen-as all anatomists must still do- heart and lungs." One may infer from this statement that Nature is the perfect contriver. " For Nature that the first real step in Harvey’s discovery was a always does that which is best," Harvey says in realisation of what was the exact nature of the one pas-4age ; "Nature does nothing in vain " he relationship which existed between heart and lungs-

venerable

must

fromi

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1000 The way had been prepared for him by Servetus and sorts and squeezing them out again as it contracted. Columbus ; both held the heretical opinion that there We feel only Harvey’s stroke of the heart--the arteries

were passages in the lungs by which blood passed from the right ventricle to the left. In this matter Fabricius was orthodox. He taught Harvey that the pulmonary artery supplied the lungs with nourishment and that the pulmonary veins served as pipes or passages-first, for the conveyance of air from the lungs to the left ventricle ; and, secondly, for the return of fuliginous vapours from the left ventricle to the lungs. The mitral valve, Fabricius held, was designed to prevent the regurgitation of air once it had entered the left ventricle. " Good God," demanded Harvey, how should the mitral valve prevent the regurgitation of air and not of blood ? " And why, if the pulmonary veins were for the conveyance of air had they not the rigid walls of the windpipe ? And why should they be filled with blood at death when they were charged with air in life ?P And why was it, when lungs were inflated in a living dog or in a dead man, that air never passed into the pulmonary veins and left ventricle ? Fabricius’ could explain none of these things. Harvey could explain all if he were allowed to presume that there were " pores " in the lung by which blood could pass from pulmonary vein. Such an assumption artery to he claimed to be legitimate, for did not everyone allow that blood percolated through liver and kidneys ? If blood could pass through the dense substances of these organs why, asked Harvey, cannot it not find its way through the porous texture of the lungs ? "

pulmonary

distending as " when a bladder is filled." We see the patient’s body as a great capillary field, uniting arteries and veins-a field of whose existence Harvey knew nothing save by inference. We think in terms of oxygen, carbon dioxide, and combustion; even Harvey had to content himself with " vital spirits " fuliginous vapours." and " innate heat." To the pre-Harveian physician the human body was a realm dominated by a cosmogony of spirits; Harvey’s greatest service to medicine was not the discovery of the circulation, but his rescue of medicine from the demonology of myth. As his method of inquiry came into fashion spirits became more and more obsolete and less and less used by anatomists for the) purpose of explanation. The spirit myth has now departed from most parts of the human body, save the brain, where it still lingers. Even Harvey himself was clearly staggered by one aspect of his discovery. When he had measured the capacity of the left ventricle and calculated its output, the amount seemed to him unnecessarily great. He found that in half an hour, with the heart beating 70 to the minute and only throwing out half an ounce at each stroke, that more than eight gallons of blood would have circled round the body. If blood was merely for the nourishment of tissues why was so much needed ? Harvey supposed that so rapid circulation was needed to keep tissues supplied with heat and vital spirits, and that the blood would congeal and thicken if not kept in active movement. More than a century after Harvey’s death vital spirits were replaced by oxygen. "

’

Study of the Living Heart in Action. All the men who taught Harvey agreed that the blood was formed in the liver, and that somehow Harvey and Darwin. it was-conveyed from the right side of the heart to There is a very remarkable parallel between the the left. The accepted opinion was that it passed " by " secret pores through the interventricular discoveries of Harvey and of Darwin-although the septum. " But, by Hercules ! " exclaims Harvey, two men represent very different physical types "no such pores can be demonstrated, nor in fact do of Englishmen. Both put forward a hypothesis to any such exist. For the septum of the heart is of a explain an enormous number of biological facts-the denser and more compact structure than any portion one to prove the truth of the circulation, the other to Before Harvey other of the body, except the bones and sinews." Harvey prove the truth of evolution. here again appeals to his argument from Nature. He men had thought of circulation of the blood, and points out that in the foetus, where the lungs are before Darwin there had been many evolutionists. silent in function, Nature has opened a passage whereby But whereas the efforts of their predecessors had blood can pass direct from the right side of the heart been tentative and not fully convincing, so overto the left ; if she had intended that blood should whelming was the proof they brought forward in pass from right to left side of the heart, not through support of their contentions that the resistance of the lungs, but direct from ventricle to ventricle, men’s minds was overborn and what had been she would certainly have provided an ample and heterodox became suddenly orthodox. Both Harvey unmistakable passage. and Darwin began by conjecture and ended by a In both cases a Anatomical conjecture can only give a clue to resorting to experimental proof. function; it can never provide the final and large presumption had to be made ; Harvey had to convincing proof. At what point of his inquiry presume that passages existed between arteries and Harvey discovered that the heart was a pump-a veins throughout the body ; Darwin had to presume double pump, the right ventricle attached to the that there was a biological process by which the lungs and the left to the rest of the body, we do not specific characters of any kind of living thing could know, but it is certain he could never have made this be altered so that a new species was produced. Such discovery unless he had studied the heart in action presumptions had to be made by both men ; only within the living body. Harvey’s mode of thinking was by making them could all the facts be explained. his own but his methods of inquiry he owed to Within three years Malpighi saw through his microFabricius. It was from his master that he learned to scope the passages which Harvey had seen only by the resort to embryology, to comparativephysiology, and eye of faith ; but although Darwin has been dead to vivisection when in search of evidence needed for these 44 years, his Malpighi has not yet made his the elucidation of all the problems of stiucture. It appearance. Some day he, too, will arrive. was to Fabricius he owed his faith in comparative physiology. What was found to be true of higher animals was certain to be directly applicable to the THE LATE DR. T. D. NICHOLSON.-After a short For Harvey, blood and spirit were case of man. Dr. Thomas Dryden Nicholson died at Brampton, illness, so were anatomy and physiology. one and inseparable ; near on April 29th. Sixty-four years of age, he He found the heart a mass of anatomical incongruities ; was aPenrith, Cumberland man and was educated at Blencow the of he handmaid by-making physiology anatomy Grammar School. His medical studies were pursued at was able to leave it a perfectly explained organ. the University of Edinburgh, and he graduated there as years spent at Bolton-onAnatomy provided him with suggestions ; physiologyill.B. in in1890. Afterheseveral settled in 1899 at Shap, where for Dearne, Yorkshire, furnished him with the proofs.

21 years he carried on a practice covering a wide and thinly Not only as medical officer and practitioner, but also as a public-spirited and active worker in many There is nothing more difficult for us moderns than causes, ‘ he was well known throughout the district, and, to feel a pulse with the finger of a pre-Harveianin 1912, lie was appointed a magistrate for the county. physician. Under his finger the artery expanded About seven years ago Dr. Nicholson moved to Brampton. of itself, drawing in blood, spirits, air and vapours of all-He leaves a widow with two sons and two daughters.

Rescue

of IVIedicine from the Demonology of lYlyth.

populated area.

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