The Works of William Harvey M.D. William Harvey
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he continues, “did I not find solace in my studies, and a balm for my spirit in the memory of my observations of former years, I should feel little desire for longer life.” (p. 145.) Let the reader turn to the page from which the above quotation is taken, and to the one which follows it, for thoughts and views that clearly bespeak the greatness of intellect, the nobleness of sentiment that distinguished William Harvey. When Ent proceeds to say that the learned world, aware of his indefatigable industry, were eagerly looking for other works at his hands, the fervid genius of the poet or discoverer still appears in his reply: “And would you be the man,” said Harvey, smiling, “who should recommend me to quit the peaceful haven, where I now pass my life, and launch again upon the faithless sea? You know full well what a storm my former lucubrations raised. Much better is it oftentimes to grow wise at home and in private, than by publishing what you have amassed with infinite labour, to stir up tempests that may rob you of peace and quiet for the rest of your days.” (p. 147.) By and by, however, he produces his Exercises on the Generation of Animals, and though he makes many difficulties at first, urging, among other things, that the work must be held incomplete, as containing nothing on the generation of insects, Ent, nevertheless, prevails in the end, and receives the papers with full authority, either speedily to commit them to the press, or to delay their publication to a future time. Ent set about his office of midwife, as he has it, forthwith, and the following year (1651) saw the birth of the work on Generation.
Physiological science generally was not sufficiently advanced in Harvey’s time to admit of a truly great and enduring work being produced on a subject so abstruse, and involving so many particulars as that of Generation. On the doctrine of the circulation the dawn had long been visible; Harvey came and the sun arose. On the subject of animal reproduction, all was night and darkness two centuries ago; and though the light has still been waxing in strength since Harvey wrote, it is only in these times that we have seen it brightening into something like the day. In Harvey’s time the very means and instruments that were indispensable to the investigation were not yet known, or were used of powers inadequate to bring the prime facts within the cognizance of the senses. Harvey doubtless did as much as any man living could have accomplished when he wrote. He announced the general truth: Omne animal ex ovo; he showed the cicatricula of the egg as the point where the reproductive process begins; he corrected numerous errors into which his master Fabricius had fallen; he further pointed out the path of observation and experiment as the only one that could lead to satisfactory results in the investigation of a subject which gradually displayed itself as one of natural history; and, it may be added, by his wanderings in the labyrinth of the metaphysics of physiological science, he did enough to deter any one from attempting to tread such barren ground again. In his work on the Heart and Blood, Harvey had all the essential facts of the subject clearly before him, and he used them at once in such masterly-wise, that he left little or nothing for addition either by himself or others. Secure of his footing here, he could well dispense with “vital spirits,” “innate heat,” and other inscrutable agencies, he could leave “adequate and efficient causes,” and other metaphysical phantoms on one side—it was physics that he was dealing with, and the physician was at home. With the information we now possess, we see clearly how indifferently weaponed was the physiologist of the year 1647 for encountering such a subject as Animal Generation; a Leeuwenhoek and a De Graaf, a Spallanzani and a Haighton, a Wolff, a Purkinje, a Von Baer, a Valentin, a Rudolph Wagner, a Bischoff, and many more, had successively to appear, before the facts of the subject could be ascertained, and a Schleiden and a Schwann were further necessary as ultimate interpreters of the things observed before they could be either rightly or wholly understood. No wonder then that The Physiologist of the 17th century, meets us in the guise of one rather puzzled with the burthen he has made up his mind to bear, and, contrary to his former wont, eking out the lack of positive knowledge by reiterated disquisitions on topics where certainty is unattainable.
It is rather curious, moreover, to find Harvey, in his work on Generation, not entirely escaping the pitfall of which he was so well aware, and which he shunned so successfully in his earlier production. In the work on the Heart, he sets out with the certainty that the whole of the notions of the ancients on the heart and blood are untenable; and then, taking Nature for his guide, his fine intellect never once suffers him to stray from the right path. In the book on Generation, on the other hand, he begins by putting himself in some sort into the harness of Aristotle, and taking the bit of Fabricius between his teeth; and then, either assuming the ideas of the former as premises, or those of the latter as topics of discussion or dissent, he labours on endeavouring to find Nature in harmony with the Stagyrite, or at variance with the professor of Padua—for, in spite of many expressions of respect and deference for his old master, Harvey evidently delights to find Fabricius in the wrong. Finally, so possessed is he by scholastic ideas, that he winds up some of his opinions upon animal reproduction by presenting them in the shape of logical syllogisms.
The age of Harvey, then, was not competent to produce a work on generation—it was still an impossible undertaking. Yet has Harvey written a remarkable book; one that teems with interesting observation, and that presents the author to us in the character of the elegant writer, the scholar, and the poet as well as the discoverer—if, indeed, poet and discoverer, though variously applied, be not identical terms. Besides the points already referred to, as immediately connected with his subject, we here find Harvey anticipating modern surgery, by applying a ligature to the main artery of a tumour which he wished to extirpate, and so making its subsequent removal much more easy. Here, too, we find him, a century and a half before his contemporaries, in the most rapidly progressive period in the history of human knowledge, throwing out the first hint of the true use of the lungs. Hitherto the lungs had been regarded as surrounding the heart for the purpose of ventilating the blood and tempering or moderating its heat, the heart being viewed as the focus or hearth of the innate heat; and Harvey himself generally uses language in harmony with these ideas; but in one instance, the lightning of genius giving him a glimpse of the truth, he says, “Air is given neither for the cooling nor the nutrition of animals * * * it is as if heat were rather enkindled within the fœtus [at birth] than repressed by the influence of the air.”[62]
Had William Harvey possessed this idea in his earlier years, and pursued it as he did that of the blood never moving in the veins but in one recurrent course, he would at least have prepared the way for another grand discovery in physiology: demonstrating the erroneousness of the current physiological notions on the use of the lungs, he would have led the van in the investigation of their proper office; and, had everything else permitted, he might even have anticipated Joseph Black in explaining the source of animal heat. But this was an impossibility at the time: chemistry, in Harvey’s day, mostly in the hands of adepts and charlatans, transmuters of the base metals, and searchers after the philosopher’s stone and the elixir of life, could have no attractions for the clear intellect of the demonstrator of the circulation of the blood. No wonder, therefore, that Harvey “did not care for chymistrey,” or that “he was wont to speak against the chymists” (Aubrey, l. c. p. 385); this anecdote is but another proof of Harvey’s sagacity. Harvey then could only show himself in advance of his age by questioning its opinions on the office of the lungs as he does; the state of chemical science in the middle of the 17th century did not admit of his doing more. Harvey, however, well knew the vivifying force of heat: he saw it the immediate indispensable agent in the reproduction of a living sentient being, as it is probably employed by the Creator as mainspring in the elaborate mechanism of the automatic animal body.
The short piece on the Anatomy of Thomas Parr, is interesting in itself; and in giving us a glimpse of Harvey’s style of pathological reasoning, confirms us in our faith in the great physiologist as a practitioner of medicine. If knowledge will not help, how should the want of it avail?
The Letters of Great men generally serve to make us more intimately acquainted with them than without such aid we could have become. This is more especially the case as respects the letters that are written in the ease and confidence of private friendship. It is greatly to be regretted that so few of the letters of this description that flowed from the pen of Harvey should have come down to us. Those addressed to Giovanni Nardi, however, show us what an affectionate and elegant mind our Harvey possessed; how mindful he always appears of former kindnesses to himself and to those that were near to him; how anxious that he should be cherished in