CHAPTER XII

THE CIRCULATION OF THE BLOOD AND THE CIRCULATION OF THE HEAVENS

The discoverer of the circulation would have been no fit pupil of Aristotle if he had limited his ken to the microcosm; nor were such limitations common in an age when astrology was not so far out of countenance as now. We have found Harvey discussing "the element of the stars" and reverently affirming the dependence of all life upon the sun as well as upon its Creator. We have found him also, in dealing with the powers of the blood, affirming that "lower and corruptible things are subject to other higher and incorruptible things," and in that connection paraphrasing a passage in which Aristotle deals with "the Cosmos which is about the earth." Of this—that is, of the sum of things between our globe and the moon's sphere—the ancient philosopher says:—

"Of necessity it is conjoined, in a way, with the courses on high, so that its entire power is governed thence; for that which originates motion in everything must be recognized as first cause."[445]

In "the courses on high" the divine living existences of heaven circulated forever, ruling the lower Cosmos as cycle succeeded cycle in endless series and the seasons endlessly recurred. In a few pregnant words Aristotle had dealt with the results of this Cosmic circulation, as follows:—

"There is said to be a circle in the affairs both of mankind and of whatever else is possessed of natural motion and is subject to generation and corruption."[446]

It was in Harvey's lifetime that this stupendous circulation of the heavens "and all that is in them" received its death stroke. Throughout Harvey's years of study at Padua, Galileo had lectured there with great acclaim; and after Harvey's return to London discovery after discovery had followed Galileo's work with the telescope, and had dealt blow after blow to the ancient astronomy. The trial of Galileo had followed; and he had died in 1642, nine years before the publication of Harvey's work On Generation. Yet belief in the ancient astronomy died far harder than belief in the ancient physiology of the movement of the blood. The ancient astronomy was based on the evidence of every man's own eyes, and flattered human vanity with the doctrine that the whole universe was centered upon the globe of which the ordained possessor was the creature made in the image of God. Milton had visited Galileo, famous long before, near Florence in 1638; but in the "Paradise Lost," published in 1667,[447] Milton expressly treated the question between the ancients and the followers of Copernicus as an open one, though Copernicus had died in 1543. Indeed, we find Harvey himself, seven years after Galileo's death, speaking of "the reason why our knowledge of the heavenly bodies is uncertain and conjectural";[448] and saying of opponents of the circulation of the blood: "Nor do they find it satisfactory to set up new systems, as in astronomy, unless these explain all the phenomena."[449]

It need not surprise us, therefore, to find Harvey writing as follows in 1628 in the very act of naming his own great discovery:—

"I beg leave to call this motion circular in the same sense in which Aristotle said that air[450] and rain imitate the circular motion of the bodies on high.[451] For the earth, when wet and warmed by the sun, gives off vapor; the vapors are borne upward and condensed and, when condensed into rain, descend again and wet the earth. Thus, too, generation here below and, in like manner, the arising of tempests and meteors result from the circular motion of the sun, his approach and recession."[452]

In 1651, nine years after the death of Galileo, in the last words about the moving blood which Harvey published, he drew a parallel between the circulation of the microcosm and the mighty circulation of the macrocosm. This parallel is drawn just before the end of his final work, his treatise On Generation, in a passage of his Exercise On the Innate Heat, in words which may serve to sum up what has gone before. These words shall be quoted without further comment and shall bring our present study of Harvey to an end:—

"The following few points should be considered well by every diligent mind, and so the fact becomes established more clearly, that those remarkable virtues which learned men attribute to the spirits and the innate heat are appropriate to the blood alone; to say nothing of what is so wonderfully striking in the egg before aught of the embryo has appeared, and in the perfect and developed embryo also. To be sure, the blood, considered absolutely and by itself outside the veins and regarded as consisting of elements[453] and as composed of different parts,—some thin and serous, some thick and solidified,—is termed 'cruor' and is possessed of very few virtues, and those obscure. But the blood, when present within the veins as a part of the body, a generative part, too, and endowed with soul, being the soul's immediate instrument and primary seat—the blood, seeming also to have a share of another diviner body and being suffused with divine heat, certainly acquires extraordinary powers, and is analogous to the element of the stars. As spirits the blood is the hearth, the Vesta,[454] the household deity, the innate heat, the sun of the microcosm, the fire of Plato;[455] not because it shines, burns, and destroys, like common fire, but because it preserves and nourishes and increases its very self by its perpetual wandering motion. Moreover, the blood deserves the name of spirits because, primarily and before all other parts, it abounds in radical moisture, that is, in the final and most immediate form of nourishment; and the same fare wherewith the blood itself is nourished is made ready by it and given out to all other parts while it is coursing perpetually through the entire body. Indeed, the blood nourishes, fosters, and keeps alive all the parts which it constructs and adjoins to itself, even as the heavenly bodies above, especially the sun and moon, impart life to what is below, while they continue in perpetual circulation. Since, therefore, the blood acts beyond the powers of the elements and is potent with those virtues aforesaid, and also is the instrument of the supreme workman, no one ever will give praise enough to its wonderful and divine faculties."[456]

Let us end these studies by picturing to ourselves the memorable figure of the small white-haired man ensconced in one of his favorite nooks on the leads of his brother's house, musing upon the mystery of the circulation, and linking it with that of

INDEX