memorative Oration which secures the pleasant gathering that year by year so worthily links the Old with the New in the College of Physicians of London. Having thus accompanied Harvey over so much of the way in his mortal career, let us, before proceeding further, briefly advert to his Writings, to the influence they had in the republic of letters during his lifetime, to the fruits they have borne since his death, and to the impression they are calculated to make on the mind that holds communion through their means with the mind that dictated them so many years ago.—The intellectual endowment of a man necessarily appears in his writings; but it is not always that from them a true conception of his general character can be formed. Harvey, however, though in his long life he accomplished but a fraction of his literary designs, has yet us enough in what he did, from which to form an esti Veritatis studens magis quam gloriæ, Industria, sagacitate, successu nobilis Circulari gyro fugientis, seque sequentis, Nec passus ultrà mortales sua ignorare primordia, Paterni Fundi ex asse hæredem collegium dicens ; Sic postquam satis sibi, satis nobis, satis gloriæ, Jun. iii, MDCLVII. left mate of him not only as a philosopher and physiologist, but, it may further be said, as a man; for ever and anon we light upon words in his works that give us assurance of his generous, upright, and truly noble nature. Let us take a survey of his writings, then, before winding up our account of his life with such personal notices as we gather from his contemporaries, or the inferences we make from his acts and written words. SECTION II. THE EXERCISES ON THE MOTION OF THE HEART AND BLOOD. Harvey's great work, though by no means the largest in bulk, is the one on the "Motion of the Heart and Blood." It has been said, happily, by a recent critical writer, that "men were already practising what Bacon came to inculcate Induction upon Data carefully collected and considered; and it would not be easy to adduce a more striking example of the way in which ultimate rational truth is reached by a succession of inferences from cognizable facts, than is contained in Harvey's Exercise on the "Motion of the Heart and Blood." Had Bacon written his Novum Organum from Harvey's work as a text, he would scarcely have expressed himself otherwise than he has done, or given different rules for philosophizing than those which will there be found enforced in practice.' In his introduction, and by way of clearing the ground, Harvey briefly exposes the views of preceding physiologists, ancient and modern, in regard to the motions of the heart, lungs and blood, to the origins and functions of the veins and arteries, the meaning of respiration, &c.-in short, he gives the accredited physiology of the thoracic viscera, with comments which show it a mass of unintelligible and irreconcilable confusion. There is room, therefore, for another interpretation of the phenomena observed, consonant with reason and anatomical fact, and susceptible of demonstration by the senses. When he first essayed himself to comprehend the motions of the heart, and to make out the meaning of these from the dissection of living animals, he found the subject so beset with difficulties that he was almost inclined to say with Fracastorius, that the motions of the heart and their purpose could be comprehended by God alone. By 1 The Novum Organum appeared in 1620. Though Harvey's work was not published till 1628, he had already developed his subject in 1615, and there is every reason to believe had actually written the Exercit. de Motu Cordis et Sanguinis before 1619. It has sometimes been made subject of question why Harvey sent his work for publication to Franckfort-on-the-Main, instead of seeing it through the press himself in London. It must have been done with a view to its getting more speedily known in the Republic of letters; Franckfort, in 1628, being the great centre of the book trade. 2 Fracastorius (Hieron). (Opera Omnia. Lugdun., 1591.) The passage here referred to by Harvey must, I presume, be the following :— "Ad priorem dilatationem sequitur attractio aeris novi, a quo refrigeratur cor; ad constrictionem vero sequitur expulsio ejusdem aeris calefacti et degrees, however, by repeating his observations and giving more concentrated attention, he at last discovers a way out of the labyrinth, and a means of interpreting satisfactorily all that had previously appeared so complicated and so obscure. Hence the occasion of his writing, and such the burden of the Introduction and first chapter of his work. This ground we have ourselves gone over in our introduction; so that we have no occasion to follow our author in his elaborate demonstration of the untenable nature of the older physiological assumptions, almost all of which had reached him with little change and small addition from the days of Aristotle and Galen. The chest of a living animal having been laid open and the pericardium removed, says Harvey, proceeding to his own views of the motions of the heart and blood, the heart is seen to be alternately in action and at rest; three principal incidents being then to be noted. Firstly, it becomes erect, strikes the chest, and gives a beat. Secondly, it is constricted in every direction-it has become notably shorter and narrower. Thirdly, grasped by the hand it is then felt to be an exceedingly firm body. From these facts we conclude simul fuliginum multorum: quæ quidem beneficia cognita a Deo et natura sunt, non autem cordi." ("Pars prima,” p. 63.) If it be soand I find no other in the book which it seems likely Harvey could have had in his eye-it appears to have been the purpose served by the attraction of air and its expulsion, along with fuliginous vapours, rather than the motions of the heart, which puzzled Fracastoro. that the action of the heart is essentially of the same nature as that of the voluntary muscles, which become hard and condensed when they act; the effect, in respect of the heart, being to lessen its bulk in every direction, to thicken and solidify its walls, and to diminish the capacity of its cavities, whereby it is made apt to expel the charge of blood it contained. The intrinsic or proper motion of the heart, therefore, is the systole; not the diastole, as hitherto imagined, when the organ is simply passive, yielding to the blood that flows into it from the veins, and having no power of expansion in itself, like the bellows of the blacksmith. The motions of the arteries again, are wholly dependent on the action of the heart. At the moment of its contraction, when the wall of the chest is struck, the arteries are distended by the wave of blood that is thrown into them and a beat or pulse is felt; facts in consonance with which the blood is seen to spurt in jets from a wounded artery synchronously with the beat of the heart. In the heart of a living animal attentively considered, two distinct motions are to be observed; one, of the auricles; another, of the ventricles, these succeeding each other rhythmically, the briefest possible pause occurring between them, the contraction of the auricles having precedence, that of the ventricles following, "like the two clacks of a water bellow," as Harvey has it in his note-book of 1616; so that if the |