The Works of William Harvey M.D. William Harvey

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opponents, who thus hastened the catastrophe of their own discomfiture, and the triumph of the truth. If men’s minds were once in danger of being led astray, it was only for an instant, and not so much through the opposition of enemies, as by an erroneous generalization, which a short interval of time sufficed to correct. Cæcilius Folius, a Venetian physician, having met with one of those anomalous instances of pervious foramen ovale in an adult, immediately and without looking farther, jumped to the conclusion that this structure or arrangement was normal, and that the blood passed in all cases by the route he had discovered, from the right to the left side of the heart. Many Italians received with favour the account which Folius immediately published of his discovery;[48] and the natural philosopher, Gassendi, having about the same period had another instance of the kind which Folius encountered, shown to him, concurred with this writer in his views, and by a variety of arguments and objections, strove to damage, and did temporarily damage, the Harveian doctrine.[49] But this was only for a brief season; for Domenic de Marchettis[50] soon after showed that Folius had mistaken an extremely rare occurrence for a general fact, and that if the open foramen ovale might afford a passage from the right to the left side of the heart in one case, closed it would suffer no such transit in hundreds of other instances. Gassendi, moreover, by getting still more out of his depth, soon afterwards showed that familiarity with general physics did not imply a particular knowledge of anatomy, nor give the power of reasoning sagely on subjects of special physiology; so that in his eagerness to assail Harvey he did injury in the end only to his own reputation. In short, Harvey in his lifetime had the high satisfaction of witnessing his discovery generally received, and inculcated as a canon in most of the medical schools of Europe; he is, therefore, one of the few—his friend Thomas Hobbes says, he was the only one within his knowledge—“Solus quod sciam,”[51] who lived to see the new doctrine which he had promulgated victorious over opposition, and established in public opinion. Harvey’s views, then, were admitted; the circulation of the blood, through the action of the heart, was received as an established fact; but envy and detraction now began their miserable work. The fact was so; but it was none of Harvey’s discovering; the fact was so, but it was of no great moment in itself, and the merit of arriving at it was small; the way had been amply prepared for such a conclusion.

      Let us look as impartially as we may at each of these statements.

      They who deny the originality of Harvey’s induction, very commonly confound the idea of a Motion of the blood, with the idea of a Continuous Motion in a Circle. It would seem that even from remote antiquity, and by common consent, mankind had recognized the blood to be in motion. We have this fact declared to us by all antiquity, and it is even particularly referred to in various passages of the grand observer of his age, the depositary of the popular science of all preceding ages—Shakespeare. Brutus speaks thus to Portia:

      “You are my true and honourable wife;

       As dear to me as are the ruddy drops

       That visit my sad heart;”

      language not more touching and beautiful than physiologically correct. And again, with more of involution and ellipsis, yet with a meaning that is unmistakable, Warwick, by the bedside of the murdered Gloster, proceeds—

      “See how the blood is settled in his face!

       —Oft have I seen a timely-parted ghost,

       Of ashy semblance, meagre, pale and bloodless,

       —Being all descended to the labouring heart,

       Who in the conflict that he holds with death,

       Attracts the same for aidance gainst the enemy;

       Which with the heart there cools, and ne’er returneth

       To blush and beautify the cheek again—

       —But see, his face is black and full of blood,” &c.

      These passages have actually been cited, to prove that Shakespeare was not unacquainted with the circulation; and there have not been wanting some[52] who have even argued that Shakespeare had his knowledge direct from the fountain-head—from Harvey himself, with whom, for several years at least, he was contemporaneous.[53]

      The passages quoted above are referred to all the more willingly, from their having preceded the teaching of Harvey by a few years only; but Shakespeare probably referred to nothing more than the accredited opinion that the blood was in motion within the vessels, particularly the veins of the body. In ancient times, indeed, the veins were regarded, as they are esteemed by the vulgar at the present hour, as the principal vessels of the body; they only were once believed to contain true blood; the arteries were held to contain at best but a little blood, different from that of the veins, and mixed accidentally in some sort with the vital spirits, of which they were the proper conduits.

      In former times, farther—times anterior to Harvey whether more remotely or more nearly—the liver, as the organ of the hæmapoësis, was regarded as the source of all the veins, i.e. of all the proper blood-vessels; the heart, as the generator of heat and the vital spirits, was viewed as the mere cistern of the blood, whence it was propelled by the act of inspiration, and whither it reverted during the act of expiration, its flow to this part of the body or to that, being mainly determined by certain excitations there inherent or specially set up. By and by, however, the liver was given up as the origin of the venous system generally; but such anatomists as Jacobus Sylvius, Realdus Columbus, Bartholomæus Eustachius, and Gabriel Fallopius, may be found opposing Vesalius in regard to the origin of the vena cava, and asserting that it takes its rise from the liver, not from the heart, as the great reformer in modern anatomy had maintained.

      In the progress of anatomical investigation, the valves in the interior of the heart, at the roots of the two great cardiac arterial trunks, and in the course of the veins at large, were perceived and their probable uses and actions canvassed. The general and prevalent notion was that they served to break or moderate the force of the current in the interior of the vessels or parts where they were encountered; though Berengarius of Carpi,[54] in describing the cardiac valves, had already said that the effect of the tricuspid valves, between the right auricle and ventricle, must be to prevent the blood in the former cavity from escaping into the latter; whilst the office of the semilunar valves, at the origins of the pulmonic artery and aorta, he declared, from their position, must be to prevent the entrance of the blood of the great arterial trunks into the heart. Fabricius, the master of Harvey, may be said to have perfected anatomical knowledge in regard to the valves of the veins—for he by no means first directed attention to their existence, or discovered them, as is generally asserted. Fabricius believed that their function was to act as obstacles to congestions of blood, as strengtheners of the veins and preventives to their becoming over-distended.

      Another long and much agitated point in the anatomy of the sanguiferous system, was the state of the septum ventriculorum of the heart, in respect of permeability or impermeability. The reason of the vast importance attached to this point was connected with the ancient, and, in Harvey’s time, generally accredited hypothesis of the Three Spirits—the natural, the vital, and the animal. The hypothesis to be brought into play, was presumed to require the intermixture in the heart of the two kinds of blood that were held appropriate to the two ventricles and to the arteries and veins respectively, and that were farther believed to meet in the cavities of the cranium, thorax, and abdomen, from which they returned to the heart by the way they came, for a fresh supply of the spirits (now exhausted or enfeebled), under the agency of which all the important operations of the body were believed to be accomplished.

      Now, Galen, the author of this hypothesis, in order to obtain an admixture of the two kinds of blood, feigned and described the partition between the two ventricles, either as perforated like a sieve, or as filled with depressions of depth sufficient to entitle them to be viewed as constituting a kind

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