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entered it by the trachea, or windpipe. the ancients had a very vague idea The conclusion was natural, in the of the necessity and the nature of early days of science, that the air, proof : so long as an opinion was thus entering by the trachea and logical and plausible, it was held to be bronchial vessels, should continue its irresistible. The spirituous element course through other vessels. When was supposed to be formed in the left the arteries of dead body were ex- ventricle of the heart; but inasmuch amined, they were found empty, and as even venous blood requires some consequently the arteries were chosen of this spirit for the purposes of as the veritable channels : hence their nutrition, it was necessary that the name (“ air-containers,” from ảnp and two bloods should mingle; and, to pew). It never occurred to the phi- meet this necessity, holes were aslosophers that air and blood might sumed in the partition dividing the both be carried along the arteries ; and two ventricles. So deeply impressed when Galen demonstrated the fact were anatomists with reverence for that the arteries did carry blood, he what Galen had said, and what theory felt bound to deny the presence of air. required, that they one and all saw the Wbat, then, becomes of the air in- holes--which do not exist. Berenger spired ? Galen said it did not enter de Carpi had, indeed, an uneasy doubt the parts of the body, but was thrown on the subject, which he naïvely exout again after performing its office, pressed in the admission that they that office being to cool the blood. were only to be seen with great diffiIf you open an artery, said Galen, culty-cum maxima difficultate vidblood will issue, but not air: whence entur; but, by straining the eyes the conclusion seems inevitable, that sufficiently, he doubtless saw what the arteries do not contain air, and do Galen required him to see—as thoucontain blood. Modern science has sands daily see what they believe they proved that atmospheric air is not ought to see. The first man who had contained in the arteries, but only sufficient strength of mind to use his the oxygen thereof, with a slight eyes, and say what he saw, was Vesaamount of nitrogen, and a certain lius* the father of modern anatomy, amount of carbonic acid gas. But as for whom Titian drew the figures the composition of the atmosphere which illustrate his work. was not suspected in the days of Thus was the second error overGalen, the presence of blood, and the thrown in 1543. The third errorabsence of air, were facts so firmly namely, that of the veins carrying established by him, that, in spite of the blood to the tissues—was someall antagonists, they finally assumed what more complex. If the venous the place of incontestable truths. and arterial bloods do not mingle in
Here, then, we see one error re- the heart, where do they mingle? moved. The others still remained. We know it is in the lungs that Galen, and all his successors, main- the one passes into the other; but it tained that the two chambers of was an immense discovery to make ; the heart communicated directly by and there is something piquant in means of holes in their septum; an the fact that it was first divined by opinion perfectly intelligible when a restless and daring theologian, we learn that it rested on a theoreti- whom Calvin burned, with affeccal assumption. Theory wanted the tionate zeal, for speculations of anfact, and men saw the fact they other kind. Michael Servetus was wanted. Theory distinguished be the first to announce the existence of tween venous blood, and spirituous the pulmonary circulation; and he or arterial blood. The venous blood announced this in the Christianismi nourished all the coarser organs, Restitutio, a work which was burned such as the liver. The spirituous by the theologians. Two copies of blood nourished all the delicate or- this work exist : one, still reddened gans, such as the lungs. In our day and partly consumed by the flames, we should demand some proof, be- is in the Royal Library of Paris ; fore accepting such a theory ; but and copious extracts from it are
* VESALIUS : Opera Omnia, edit. 1725, i. 519.
printed by M. Flourens in his “His- seen in the fact of its being also tory." Nothing can be less equivo- made by Cæsalpinus, the great boeal than the description given by tanist, who does not seem to have Servetus of the passage of the blood been aware of what Colombo had from the heart to the lungs, “where written, since he makes no menit is agitated, prepared, changes its tion of him, and as M. Flourens obcolour, and is poured from the pul- serves, le grand mérite est toujours monary artery into the pulmonary probe. Cæsalpinus, moreover, was vein." *
the first to pronounce the phrase This idea was as novel as it was “ circulation of the blood.” I true; but we cannot agree with M. Here the reader may ask, What Flourens in regarding this as a dis- further remained for Harvey to discovery, in the strict sense of the cover ? and it may surprise him to term; for although Servetus had hear the answer : Everything ! Such some notion of the anatomical evi- is pretty nearly the fact. The puldence furnished by the large calibre monary circulation takes place only of the pulmonary artery, which en- through a small arc of the great ables it to carry a far greater quan- circle traversed by the blood. Betity of blood than could be needed sides this arc, there is theother greater for the nutrition of the lungs, yet arc, through which the systemic, or we have only to read the passages in general circulation, takes its course; which he describes this pulmonary and of this no one except Cæsalpinus circulation to perceive that he had had even a suspicion. Every one no accurate idea of it: he speaks supposed that the veins carried the confidently of the nerves being con- blood to the tissues, and nourished tinuations of the arteries, and de- them ; no one suspected that this scribes with grave precision how the function was reserved for the arteair passes from the nose into the ries, and that the veins carried the ventricles of the brain, and how the blood only to the heart. It was devil takes the same route to lay thought that the arteries had their siege to the soul. All we can say is, origin in the heart, and the veins in that Servetus made one lucky guess the liver ; from the liver the veins among his numerous guesses by no carried the blood to every part. A means of the lucky kind. He an- single fact, familiar to every surgeon, nounced the fact of the pulmonary and to every barber who ever opencirculation, and may receive from ed a vein, ought to have revealed History the whole credit of such the error ; since every tiine a ligature priority; he also guessed rightly was applied, the operator must have that in the lungs, and not in the seen that the vein swelled below the liver, the blood received its elabora- ligature, and not above it, from which tion, passing from venous into arte- the deduction seems obvious that the rial. But whatever merit may be blood in the vein flowed to the heart, assigned to Servetus, no influence and not from it. But here, as in so can be attributed to his discovery, many other cases, familiar facts were since both he and his treatise were not observed ; they were seen, but roasted by Calvin, and no one heard not interpreted. Cæsalpinus was the of the pulmonary circulation. Six first who observed it, but he has years afterwards, Realdo Colombo only the merit of having suspected rediscovered the pulmonary circula- the cause to be the current setting tion;t and that the discovery was towards the heart. His suspicion ready to be made on all sides, is was not a demonstration ; and we are
* “ Fit autem communicatio hæc, non per parietem cordis medium, ut vulgo creditur. Sed magno artificio a dextro cordis ventriculo, longo per pulmones ductu, agitatur sanguinis subtilis : a pulmonibus præparatur,' flavus efficitur, et a vena arteriosa in arteriam venosam transfunditur."
+ COLUMBO : De re Anatomicâ, edit. 1572, p. 325.
I CÆSALPINUS : Quæst. Peripitet., edit. 1593, lib. v. p. 125. Flourens gives the passage, as well as that from Colombo.
§ "Quia tument venæ ultrà vinculum, non citra. Debuisset autem opposito modo contingere, si motus sanguinis et spiritus a visceribus fit in totum corpus." - Quæstionum Medicarum, lib. ii. p. 234.
surprised to find De Blainville saying, Harvey having had a clear idea of " that the circulation was known to the true theory, no one had even acCæsalpinus, although he had not de- curately conceived the true theory of monstrated it.” In science, the dif- pulmonary circulation ; for although ference between a guess and a de- Servetus, Colombo, and Cæsalpinus monstration is as great as that be- knew that the blood passed through tween the fame which an unwritten the lungs, they fancied only so much poem may achieve, and the fame passed as was necessary for the rewhich a great poem has achieved. If ception of the “ vital spirits,” guesses counted as achievements, the quantity which their predecessors temple of fame would be thronged fancied took its course through the with the statues of heroes. De perforated septum of the heart. But Blainville says, that the reason why they had no conception of the entire Haller and others have denied the mass of blood traversing the lungs; claim of Cæsalpinus, is because they and even had they known so much, did not read what he had said in they would have been wholly at a loss his work On Plants.* Now, if to say whence it came, and whither we turn to the passage in ques- it went. It was necessary to undertion,+ we shall see how far the stand the whole circulation before any writer really was from the truth, and part of it could accurately be underyet how near his guess went to the stood. truth. In animals, we see the food The discovery that the veins had carried by the veins to the heart, as valves, opening and closing like to a centre of innate heat; and there, doors, brought the discovery of the having acquired its final perfection, circulation within compass. It was it is distributed over the whole body made in 1574 by Fabrice d'Acquathrough the arteries, by the agency of pendente, under whom Harvey studthe spirit, which is engendered in the ied at Padua. These valves, preheart by this same food.” Easy as it venting any flow from the heart, is for us to read into this passage al- but admitting the flow to the heart, most all that we understand by the ought to have suggested to their discirculation, a close historical criticism
coverer the true interpretation of detects in it nothing but a guess ; their use.
But five-and-forty years and, as Bérard remarks, we ought elapsed before any one arose, who not to confound two such vague had the sagacity to perceive the real statements as these, themselves re- value of this anatomical structure in quiring demonstration, and by Cæs- respect to the blood-currents; and alpinus himself subsequently contra- during these five-and-forty years, dicted, with the clear ideas, and everything that had been discovered imposing proofs, on which Harvey or surmised respecting the circulaestablished his discovery." The con- tion, was familiar to every anatomist vincing, evidence of Harvey's origi- of the great Paduan school in which nality is, that not only was this Harvey studied : nevertheless, when guess advanced by Cæsalpinus with- Harvey promulgated his theory, it out any influence on the theories of was vehemently opposed. In 1619 that day, in spite of his deserved he first publicly taught what he had authority; but when Harvey promul- discovered ; and in 1628 he publishgated his theory, he found, all over ed, for the benefit of Europe, his ceEurope, the greatest difficulty in lebrated treatise, Exercitatio Anatogetting it accepted. Bérard main- mica de Motu Cordis et Sanguinis, tains, that so far from any one before which may justly be called the basis
DE BLAINVILLE: Hist. des Sciences de l'Organization, ii. 227-a statement repeated by ISIDORE GEOFFROY ST HILAIRE : Histoire Générale des Règnes Organiques, i. 44.
+ CÆSALPINUS: De Plantis, i., c. 2, p. 3.-"In animalibus videmus alimentum per venas duci ad cor tanquam ad officinam caloris insiti, et adeptâ inhibi ultimâ perfectione, per arterias in universum corpus distribui agente spiritu, qui ex eodem alimento in corde gignitur."
I BERARD: Cours de Physiol., iii. 581. MILNE EDWARDS : Leçons sur la Phys.et l'Anat. comparée, iii. 20.
of modern physiology. That the the- brachio - cephalic, spinal, and iliac ory was new, and would be opposed veins, and they are rarely present in as a heresy, no one more clearly di- the azygos and intercostal veins. vined than he did.* The greatness M. Flourens says, that when Harof the discovery, and the force of vey appeared everything had been genius required to make it, can only suspected or indicated, but nothing be appreciated by those who, familiar established. This seems to us even with the state of opinion in those less than the truth, for we cannot days, read the evidence and argu- persuade ourselves that any one had ments by which Harvey established the slightest conception of the prohis doctrine. It is true that he ap- Acquapendente could make peared at a peculiar epoch, when the nothing of the valves he had detectconfluence of various discoveries ren- ed. He thought their office was dered his discovery possible ; but simply to prevent a too great accuthat a man of genius was necessary mulation of blood in the lower parts to interpret and co-ordinate those of the body and a diminution from discoveries, is evident in the fact, that the upper parts. Colombo thought no one except Harvey had, for nearly with his contemporaries, that the half a century, seen the significance veins had their origin in the liver, of the facts.
and carried blood to the tissues. Here, however, a caution must be Cæsalpinus, in spite of his recognition interposed. The importance of the of pulmonary circulation, thought the valves has been greatly exaggerated, blood also passed from the right and their real bearing on Harvey's chamber of the heart to the left
. discovery misconceived. They are But Harvey not only conceived a thought to have rendered the dis- clear idea of the process, he decovery facile, because, inasmuch as scribed it minutely and accurately. they prevent the blood from flow- He noticed the successive contracing backwards, while permitting it to tions of each auricle and ventricle, flow outwards, the idea of the circula- which forced the blood into the vention, it is said, must necessarily have tricle, when the auricle contracted, emerged from the contemplation of and forced it from the ventricle into them. Against this supposition there the lungs, when the ventricle contractis one decisive fact : no one did de- ed: a process repeated on the left side duce the conclusion, which is thus with the aerated blood. And at each said to lie so ready. Moreover, in passage of the blood from one cavity many cases, circulation takes place to another, there were the valves, or entirely without their aid. There are "little doors” (ostiola) opening to let no valves in the veins of the Inverte- the current pass, and closing to prebrata,t none in the veins of fishes vent its reflux.' He described the and reptiles, and very few in birds; course of the blood along the arteries, yet the circulation is as complete in which he attributed to the pulsations these animals as in man. Nay, even of the heart; and in this, instead of in man the chief veins are destitute in Galen's “pulsific virtue,” he reof valves, although writers on Natural cognised the cause of the blood's Theology, and even better-informed movement. physiologists, are in the habit of By Harvey the overthrow of anspeaking of them as if they were uni- cient authority was completed. Men versal and indispensable"; it may, dared no longer swear by Galen—they therefore, be useful to mention, that swore by Harvey, who had discovthere are no valves whatever in the ered the greatest fact in the animal great venous trunks—the venæ cave, economy, a fact totally unknown and and portal veins -none in the hepatic, unsuspected by Galen, or any other renal, and uterine veins-none in the ancient. The new era had commenced. It was not in the nature and its bearing on the theory of the of things for the old system quietly circulation will be appreciated by to accept the new; accordingly, the any one who reflects on the fact that opposition was loud and vehement. venous and arterial blood being so Like many other parts of this history, obviously distinguished, it is necesand like most oppositions to new sary that the passage of the one into doctrines, it has been immensely ex- the other should be demonstratedaggerated by historians, and by not surmised—before the theory of writers who have chosen it as a theme the circulation can be accepted as for rhetoric. It is true that the complete; for any one might reasonFaculty rejected the new doctrine. ably assume that the blood in the But it is no less true that eminent veins is altogether another fluid from men accepted it with enthusiasm. that in the arteries, and not merely If Guy Patin was caustic in opposi- another state of that fluid. This, intion, Molière laughed at Guy Patin's deed, was assumed by the adversaries prejudice; and Boileau ridiculed the of Harvey, and has found supporters Faculty. Some anatomists accepted even in our own day. Burdach cites the doctrine, and the great Descartes two German physiologists – Willwarmly espoused it.* Swammer- brand and Runge-whom he thinks damm and Malpighi, two of the great worthy of refutation, and who mainnames of the century, speak of Har- tained that arterial blood was transvey with reverence; and soon no one formed in a mass into the tissues, spoke of him in any other tone. and that venous blood was the re-trans
*“Adeo iis nova erunt et inaudita, ut non solum ex invidia querundam metuam malum mihi, sed vereor ne habeam inimicas omnes homines, tantum consuetudo aut seinel inhibita doctrina, altisque defixa radicibus, quasi altera natura apud omnes valet, et antiquitatis veneranda opinio cogit.”—Exercit. p. 88.
+ In the aorta of the Eolis there is a semilunar valve.
It is impossible to read Harvey's formed tissues. Unless the passage work without the highest admiration of the blood into the veins be clearly for the scientific genius it displays, traced, there can be no reason against and the conviction that here the cir- supposing that the veins simply abculation was not only demonstrated, sorb from the tissues, in the same but for the first time conceived. The way as the lymphatics and lacteals experiments and arguments by which absorb their fuid. To prove that he establishes the fact, are still the blood makes a circuit, that cirworthy of study, as models of inves- cuit must be traced; and Harvey tigation. But there were necessary plainly declares that, with all his gaps in his doctrine. The course of diligence, he could not succeed in the circulation was not known to tracing any connection between arhim, could not indeed have been dis- teries and veins ; in only three covered by any instruments at his dis- places did he find them presenting posal. He supposed the blood passed anything like an anastomosis ; in from arteries to veins by two paths, every other place he imagined poroeither through anastomosis (that is to sities. say, the arteries opening directly into Nor, with the means at his disveins), or through the porosities of posal, could Harvey have traced the the parts—aut porositates carnis et complete course of the blood. The partium solidarum pervias sanguini. Microscope was needed ; and the He thought it necessary that so first to employ the microscope in such much of the blood as was required researches was Malpighi, who, four by the tissues for their nutrition, years after Harvey's death, in 1661, should remain behind in the tissues, detected those capillaries which form and the rest be carried onwards to the channel of communication bethe heart. The error is considerable; tween arteries and veins. He says
* The culpable carelessness with which history is often written, is exhibited in the criticism of M. ISIDORE ST HILAIRE : Hist. des Règnes Organiques, i. 49; on the passage in CUVIER, Hist. des Sciences Nat., ii. 53, where Harvey is said to have the rare happiness of seeing his discovery accepted by Descartes. M. St Hilaire remarks that this is an error, because Harvey died in 1657, and Descartes did not publish his Traité de l'Homme until 1662. This remark is doubly unfortunate, Descartes having expressed his adherence to the doctrine in his very first work, Discours de la Méthode ; and Harvey having, in his Second Reply to Riolan, expressed his gratification at this flattering approval of Descartes.