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

"The shining powers, conspicuous afar Against the ether, which to mortals bring Winter and summer."[457]

NOTES

[1] In the present paper frequent references will be made to the writings of Harvey, Galen, Aristotle, and Hippocrates. Citations from these authors will be made from the following editions:--

References to Harvey's finished writings will be made to two editions, viz.: The Works of William Harvey, translated from the Latin with a life of the author by R. Willis, M.D., London, 1847, printed for the Sydenham Society, which will here be designated as "Syd."; and Guilielmi Harveii Opera Omnia: A Collegio Medicorum Londinensi Edita: 1766, which will be designated as "Op. Omn." In the preparation of the text the present writer has used these two editions and also the first editions of Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, Frankfort, 1628, and Exercitationes de Generatione Animalium, London, 1651. Willis's translation of passages has been revised, often freely, where the writer has judged this desirable; and sometimes the revision amounts to a fresh translation. References to Harvey's lecture notes will be made to Prelectiones Anatomiæ Universalis by William Harvey, edited with an autotype reproduction of the original by a committee of the Royal College of Physicians, London, 1886.

References to Galen's writings will be made to two editions, viz.: Claudii Galeni Opera Omnia. Editionem curavit C. G. Kühn, Leipsic, 1821-1833, which will be designated by the letters "Kn."; and Œuvres Anatomiques, Physiologíques et Medicáles de Galien, Traduites avec Notes par C. Daremberg, Paris, 1854-1856, which will be cited as "Dar." The former is the recognized working edition of the Greek text of Galen; this is accompanied by a Latin translation, to which is appended a serviceable Latin index. By the pages of this edition the Greek text of Galen is commonly cited. None of the treatises of Galen has been translated into English. Some of those most interesting to physiologists may be read in the above French translation of Daremberg. A critical edition of the Greek text of Galen's treatise On the Doctrines of Hippocrates and Plato, Claudii Galeni de Placitis Hippocratis et Platonis, with an amended Latin translation by Johannes Müller, was published by Teubner, Leipsic, 1874; it will here be cited as "Mül."

References to Aristotle's writings will be made to Aristotelis Opera: Edidit Academia Regia Borussica, Berlin, 1831-1870, which is the commonly cited Greek text. Pages and lines of this edition will always be found in the margin of a modern edition or translation. The following works of Aristotle will be referred to in this paper:--

The Psychology and its appendices, viz.: the so-called "Lesser Works on Natural Things (Parva Naturalia)." English translation by W. A. Hammond, New York, 1902. The two last treatises of the Parva Naturalia have also been translated by W. Ogle, M.D., London, 1897.

The History of Animals. English translation by R. Creswell. Bohn's Classical Library. London, 1878.

On the Parts of Animals. English translation by W. Ogle, M.D., London, 1882.

On the Generation of Animals. There is no English translation. An excellent German translation, with the Greek text, is that by Aubert and Wimmer, Leipsic, 1860.

Physics. There is no English translation; Greek text and German translation by C. Prantl, Leipsic, 1854.

On Heaven: On Generation and Corruption (In the Universe at Large). There is no English translation; Greek text and German translation by C. Prantl, Leipsic, 1857.

Meteorology. There is no English translation; French translation by J. B. St. Hilaire, Paris, 1863.

Besides the foregoing, other treatises by Aristotle may be referred to or cited briefly.

References to the Hippocratic writings will be made to Œuvres Complètes d'Hippocrate, traduction nouvelle, par É. Littré, Paris, 1839-1861, which will be designated as "Lit." This is the standard working edition of the Greek text of the Hippocratic collection, and is the one now usually cited. The accompanying French translation is complete. There is a translation into English of some of the treatises, but it cannot be recommended. A new version of the Greek text is now in slow course of publication by Teubner of Leipsic.

[2] John Aubrey: 'Brief Lives,' Chiefly of Contemporaries, etc. Edited from the Author's Mss. by Andrew Clark; 1898, Vol. I, 300.

[3] Harvey: On Generation, Preface, Syd. 152, l. 34 to 153, l. 4; Op. Omn. 168, l. 22-26.

[4] Galen: Is Blood Naturally Contained in the Arteries? Kn. Vol. IV, 703-736.

[5] Harvey: On Conception, Syd. 575, l. 9-12; Op. Omn. 592, l. 8-11.

[6] Harvey: Letter to Hofmann, Syd. 595, l. 6-15; Op. Omn. 635, l. 10-17.

[7] Harvey: Letter to Hofmann, Syd. 596, l. 3-7; Op. Omn. 636, l. 1-4.

[8] Harvey: Exercise to Riolanus, II, Syd. 122, l. 31 to 123, l. 1; Op. Omn. 122, l. 16-21.

[9] Harvey: On the Motion, etc., VIII, Syd. 47, l. 29-33; Op. Omn. 49, l. 28-30.

[10] Harvey: On the Motion, etc., IX, Syd. 48, l. 10-14; Op. Omn. 50, l. 8-11.

[11] Plato: Timæus, 70_a_ and _b_; 77_c_ to 78_a_; 78_e_ to 79_a_.

Aristotle: On the Parts of Animals, 668_a_, 4 to _b_, 6.

Galen: On the Natural Faculties, Kn. Vol. II, 210-212; Dar. Vol. II, 318.

[12] Aristotle: On Sleep and Waking, 456_a_, 30 to _b_, 5.

Galen: On the Use of the Parts, etc., Kn. Vol. III, 269-270; Dar. Vol. I, 280-282.

[13] Galen: On the Natural Faculties, Kn. Vol. II, 186-189; Dar. Vol. II, 306-307.

[14] Harvey: On the Motion, etc., Syd. 72, l. 24 to 73, l. 12; Op. Omn. 73, l. 26 to 74, l. 15.

[15] Harvey: On the Motion, etc., Syd. 75, l. 9-22; Op. Omn. 76, l. 15-25.

[16] Joannes Riolanus, Filius: Encheiridium Anatomicum et Pathologicum, etc., Paris, 1648, 298, l. 1-4. Harvey's quotation does complete justice to the sense, but is by no means accurate verbally.

[17] Harvey: Exercise to Riolanus, I, Syd. 95, l. 4-21; Op. Omn. 97, l. 6-23.

[18] Aselli: De Lactibus, sive Lacteis Venis, etc. Milan, 1627.

[19] John Aubrey: Brief Lives, etc., 1898, Vol. I, 302.

[20] Harvey's venous artery and arterial vein correspond respectively to the pulmonary vein and the pulmonary artery of our nomenclature.

[21] Harvey: On the Motion, etc., VI, Syd. 39, l. 29 to 40, l. 15; Op. Omn. 41, l. 20 to 42, l. 10.

[22] Compare Aristotle: History of Animals, 511_b_, 10-24.

[23] Harvey: On the Motion, etc., XVII, Syd. 85, l. 17-25; Op. Omn. 87, l. 5-12.

[24] Aristotle: On Youth and Old Age, On Life and Death, 469_b_, 6-20.

[25] Aristotle: On Respiration, 473_a_, 8-10.

[26] Aristotle: On the Generation of Animals, 732_a_, 18-20.

[27] Aristotle: On Youth and Old Age, On Life and Death, 469_a_, 28 to 470_a_, 18. On Respiration, 474_a_, 25 to _b_, 24; 478_a_, 26 to _b_, 21; 480_a_, 18 to _b_, 20.

[28] Aristotle: On Respiration, 478_a_, 21-30.

[29] διὰ τὴν σύναψιν.

[30] Aristotle: History of Animals, 496_a_, 27-32.

[31] Hippocrates: On the Heart, Lit. Vol. IX, 86 and 90-92.

[32] Hippocrates: On the Heart, Lit. Vol. IX, 86-88.

[33] Galen: On the Use of Respiration, Kn. Vol. IV, 487-493.

[34] ποιότητος.

[35] Galen: Is Blood Naturally Contained in the Arteries? Kn. Vol. IV, 724-725.

[36] Galen: On the Use of Respiration, Kn. Vol. IV, 510.

[37] Galen: On the Use of the Parts, etc., Kn. Vol. III, 412; Dar. Vol. I, 381.

[38] Galen: On the Use of the Pulse, Kn. Vol. V, 149-180.

[39] Harvey: On the Motion, etc., Preface, Syd. 9-14; Op. Omn. 9-14.

[40] Galen: On the Use of the Parts, etc., Kn. Vol. III, 636-656; Dar. Vol. I, 541-552.

[41] Harvey: Prelectiones, 86 right.

[42] Compare Hippocrates: On Flatus, Lit. Vol. VI, 96.

[43] Harvey: Prelectiones, 86 right.

[44] Galen: On the Use of Respiration, Kn. Vol. IV, 470-471.

[45] Harvey: Prelectiones, 86 right.

[46] Aristotle: On Respiration, 473_a_, 15 to 474_a_, 24. Hippocrates: On the Sacred Disease, Lit. Vol. VI, 368 and 372.

[47] Hippocrates: On the Sacred Disease, Lit. Vol. VI, 368.

[48] Passages which justify the statements here made are among those cited in note 140.

[49] Galen: Is Blood Naturally Contained in the Arteries? Kn. Vol. IV, 703-736.

[50] Galen: On the Use of the Parts, etc., Kn. Vol. III, 541-542; Dar. Vol. I, 476.

[51] Plato: Timæus, 69_c_-_d_. Archer-Hind's Edition, 254, l. 13 to 256, l. 6.

[52] Aristotle: On Soul, 412_a_, 1 to 415_a_, 13.

[53] Galen: On the Doctrines of Hippocrates and Plato, Kn. Vol. V, 608.

[54] Galen: On the Use of the Parts, etc., Kn. Vol. III, 696-703; Dar. Vol. I, 575-579. See also Rapp: "Ueber das Wundernetz," Meckel's Archiv für Anatomie und Physiologie, 1827, 1-13.

[55] Galen: On Methods of Treatment, Kn. Vol. X, 839-840.

[56] On the subject of the spirits the following passages of Galen's works should be consulted, viz.:--On the Natural Faculties, Kn. Vol. II, 204, l. 11 to 206, l. 13; Dar. Vol. II, 315, l. 7 to 316, l. 14; Kn. Vol. II, 214, l. 9-16; Dar. Vol. II, 320, l. 2-9. On the Organ of Smell, Kn. Vol. II, 857-886. On the Use of the Parts of the Human Body, Book VI: Kn. Vol. III, 412, l. 6-12; Dar. Vol. I, 381, l. 4-9; Kn. Vol. III, 487, l. 3 to 488, l. 13; Dar. Vol. I, 438, l. 1 to 439, l. 9; Kn. Vol. III, 490, l. 14 to 492, l. 8; Dar. Vol. I, 440, l. 24 to 441, l. 16; Kn. Vol. III, 496, l. 5-16; Dar. Vol. I, 444, l. 6-19. Book VII: Kn. Vol. III, 536-544; Dar. Vol. I, 472-477; Kn. Vol. III, 544-549; Dar. Vol. I, 477-480. Book VIII: Kn. Vol. III, 636-651; Dar. Vol. I, 541-550; Kn. Vol. III, 651-656; Dar. Vol. I, 550-552; Kn. Vol. III, 663; Dar. Vol. I, 557; Kn. Vol. III, 672-673; Dar. Vol. I, 563. Book IX: Kn. Vol. III, 684-691; Dar. Vol. I, 569-572; Kn. Vol. III, 696-703; Dar. Vol. I, 575-579; Kn. Vol. III, 750-751; Dar. Vol. I, 602-603. Book XIV: Kn. Vol. IV, 183, l. 7-10; Dar. Vol. II, 114, l. 23-25. Book XVI: Kn. Vol. IV, 323, l. 2-18; Dar. Vol. II, 189, l. 3-21; Kn. Vol. IV, 333, l. 18 to 335, l. 10; Dar. Vol. II, 195, l. 6-36. Book XVII: Kn. Vol. IV, 349, l. 5-14; Dar. Vol. II, 202, l. 30-38. On the Causes of Respiration, Kn. Vol. IV, 465-469. On the Use of Respiration, Kn. Vol. IV, 470-511. Is Blood Naturally Contained in the Arteries? Kn. Vol. IV, 703-736. On the Use of the Pulse, Kn. Vol. V, 149-180. On the Doctrines of Hippocrates and Plato, Book II: Kn. Vol. V, 281, l. 3-15; Mül. 245, l. 10 to 246, l. 6. Book III: Kn. Vol. V, 355, l. 18 to 356, l. 11; Mül. 325, l. 16 to 326, l. 9. Book VI: Kn. Vol. V, 524, l. 12 to 525, l. 16; Mül. 512, l. 3 to 513, l. 8; Kn. Vol. V, 571, l. 12 to 573, l. 2; Mül. 563, l. 12 to 566, l. 2. Book VII: Kn. Vol. V, 600-611; Mül. 596-608; Kn. Vol. V, 611-617; Mül. 608-615; Kn. Vol. V, 628, l. 8-15; Mül. 626, l. 8-15; Kn. Vol. V, 641, l. 14 to 642, l. 6; Mül. 641, l. 13 to 642, l. 6. Book VIII: Kn. Vol. V, 707, l. 17 to 710, l. 15; Mül. 714, l. 14 to 718, l. 2. On Methods of Treatment, Book IX: Kn. Vol. X, 635, l. 6 to 636, l. 12. Book XII: Kn. Vol. X, 839, l. 10 to 840, l. 3.

[57] Harvey: Prelectiones, 83 right.

[58] Harvey: Prelectiones, 85 left.

[59] Harvey: Prelectiones, 83 right and 85 left.

[60] Compare R. Columbus: De Re Anatomica. Venice, 1559, 223-224.

[61] Harvey: Prelectiones, 85 left. The last line of page 85 left, as deciphered and printed, reads as follows: "Galenus 7 & p. 8°." It should read, however, "Galenus 7 u.p. 8°." That this is Harvey's brief reference to Galeni Lib. 7, De Usu Partium, Cap. 8, is proved by the text of the Galenic passage thus referred to, viz.: Galen: On the Use of the Parts, etc., Kn. Vol. III, 539-540, Dar. Vol. I, 475.

[62] As no other claimant than Columbus to be the discoverer of the pulmonary transit of the blood was known to Harvey, the question whether Columbus was the true discoverer, or possibly owed the basis of his doctrine to the unfortunate Michael Servetus, need not here be discussed.

[63] Vesalius: De Humani Corporis Fabrica, Basel, 1543; Lib. VI, Cap. II, 589, l. 9-24. Vesalius: Opera Omnia Anatomica et Chirurgica, Leyden, 1725, Tom. I, De Hum. Corp. Fabr. Lib. VI, Cap. 11, 511, l. 11-23; Cap. 15, 519, l. 42-54. Columbus: De Re Anatomica, Lib. VII, 177, l. 17-24.

[64] Aristotle: On the Parts of Animals, 649_b_, 19-27.

[65] Harvey: Prelectiones, 85 right. Compare closely similar passages in Harvey: On the Motion, etc., Introduction, Syd. 12, l. 9-15; Op. Omn. 12, l. 10-17. Exercise to Riolanus, II, Syd. 116, l. 26-33; Op. Omn. 116, l. 15-20. On Generation, LXXI, Syd. 504, l. 22-28; Op. Omn. 525, l. 23-29.

[66] The decipherer of Harvey's Ms. notes reads "_generatur_."

[67] Harvey: On the Motion, etc., Introduction, Syd. 18, l. 16-21; Op. Omn. 18, l. 17-21.

[68] Compare Aristotle: On Respiration, 470_b_, 28 to 471_b_, 29.

[69] Harvey: Prelectiones, 86 left.

[70] Harvey: On the Motion, etc., Introduction, Syd. 16, l. 23-27; Op. Omn. 16, l. 21-26.

[71] Harvey: On the Motion, etc., Introduction, Syd. 16, l. 28-39; Op. Omn. 16, l. 27 to 17, l. 4.

[72] πνεῦμα.

[73] Aristotle: History of Animals: 496_a_, 27-32.

[74] Columbus: De Re Anatomica, Lib. VII, 178-180; Lib. XI, 223-224; Lib. XIV, 259 and 261.

[75] Harvey: Prelectiones, 86 left.

[76] Galen: On the Doctrines of Hippocrates and Plato, Kn. Vol. V, 611-617; Mül. 608-615.

[77] Harvey: Prelectiones, 94 right: "_puto: spiritus Nervis non progredi sed Irradiatos et actus fieri unde sensus et motus ut lumen in aere: forsan ut fluxus et refluxus Maris_," etc.

[78] Harvey: Exercise to Riolanus, II, Syd. 118, l. 9-14; Op. Omn. 117, l. 29-32.

[79] Harvey: Prelectiones, 86 left.

[80] Columbus: De Re Anatomica, Lib. VI, 166-167; Lib. VII, 177-178; Lib. XI, 22.

Harvey: On the Motion, etc., VII, Syd. 41, l. 7-14; Op. Omn. 43, l. 3-9.

[81] Harvey: Exercise to Riolanus, I, Syd. 98, l. 16-23; Op. Omn. 100, l. 21-28.

[82] Harvey: Exercise to Riolanus, II, Syd. 113-121; Op. Omn. 113-121. On Generation, LXXI, Syd. 501-512; Op. Omn. 523-534.

[83] Harvey: On Generation, LXXI, Syd. 502, l. 33-37; Op. Omn. 524, l. 5-7.

[84] Harvey: On Generation, LXXI, Syd. 504, l. 22-31; Op. Omn. 525, l. 25-32.

[85] Harvey: Exercise to Riolanus, II, Syd. 118, l. 32-38; Op. Omn. 118, l. 16-19.

[86] Harvey: Exercise to Riolanus, II, Syd. 119, l. 3-5 and l. 10-17; Op. Omn. 118, l. 26-28 and 118, l. 30 to 119, l. 4.

[87] Harvey: Prelectiones, 86 right.

[88] Harvey: Exercise to Riolanus, II, Syd. 113, l. 28 to 114, l. 19 and 117, l. 35 to 118, l. 9; Op. Omn. 113, l. 22 to 114, l. 14 and 117, l. 19-29.

[89] Harvey: On Generation, LII, Syd. 388, l. 31-32; Op. Omn. 405. l. 14-15.

[90] Harvey: On Generation, LII, Syd. 386, l. 11-12; Op. Omn. 402, l. 24-26.

[91] Harvey: Prelectiones, 87 left.

[92] Galen: On the Doctrines of Hippocrates and Plato, Kn. Vol. V, 571-572; Mül. 563, l. 12 to 565, l. 9.

[93] Harvey: Exercise to Riolanus, II, Syd. 114, l. 26-29; Op. Omn. 114, l. 19-21.

[94] Harvey: Exercise to Riolanus, II, Syd. 114, l. 37-40; Op. Omn. 114, l. 28-31.

[95] Harvey: Exercise to Riolanus, II, Syd. 115, l. 18-21; Op. Omn. 115, l. 12-14.

[96] Harvey: Exercise to Riolanus, II, Syd. 136, l. 19-21; Op. Omn. 136, l. 12-13.

[97] Harvey: On the Motion, etc., XVII, Syd. 77, l. 24-29; Op. Omn. 79, l. 5-9.

[98] See J. C. Dalton: Doctrines of the Circulation, Philadelphia, 1884, 127-128.

[99] Columbus: De Re Anatomica, Lib. XI, 223, l. 11 to 224, l. 8.

[100] Galen: On the Use of the Parts, etc., Kn. Vol. III, 451-452; Dar. Vol. I, 412, l. 5-8.

[101] Harvey: Letter to Slegel, Syd. 597, l. 14-23; Op. Omn. 613, l. 19-27.

[102] Harvey: On Parturition, Syd. 530, l. 3-10 and l. 25-36; Op. Omn. 549, l. 22-27 and 550 l. 11-20.

[103] Harvey: Letter to Hofmann, Syd. 596, l. 3-7; Op. Omn. 636, l. 1-4.

[104] Harvey: Exercise to Riolanus, II, Syd. 123, l. 15-18; Op. Omn. 122, l. 31 to 123, l. 1.

[105] Harvey: On the Motion, etc., IX, Syd. 48, l. 21 to 50, l. 36; Op. Omn. 50, l. 17 to 52, l. 23.

[106] Harvey: Prelectiones, 80 right.

[107] Hippocrates: On Wounds, Lit. Vol. VI, 430.

[108] Hippocrates: Epidemics, Lit. Vol. V, 114-116. Compare Galen's Third Commentary on Epidemics, Kn. Vol. XVII, A., 433, l. 14 to 436, l. 2.

[109] Harvey: Prelectiones, 79 right.

[110] Harvey: Exercise to Riolanus, II, Syd. 140, l. 30-39; Op. Omn. 140, l. 23-31.

[111] Harvey: Exercise to Riolanus, I, Syd. 98, l. 9-23; Op. Omn. 100, l. 14-28.

[112] Hippocrates: On the Heart, Lit. Vol. IX, 84, l. 11-12.

[113] Aristotle: On Youth and Old Age, etc., 469_b_, 6-20.

[114] Aristotle: On the Parts of Animals, 670_a_, 23-26.

[115] Galen: On the Use of Respiration, Kn. Vol. IV, 505, l. 15 to 506, l. 5.

[116] Harvey: On the Motion, etc., VIII, Syd. 46, l. 34 to 47, l. 16; Op. Omn. 49, l. 3-19.

[117] Aristotle: On Respiration; On the Parts of Animals, Books II and III; and elsewhere. This reference is by Harvey himself.

[118] Aristotle: On the Parts of Animals, Book II. This reference is by Harvey himself.

[119] Harvey: On the Motion, etc., XV, Syd. 68, l. 19 to 69, l. 17; Op. Omn. 69, l. 22 to 70, l. 18.

[120] Harvey: On the Motion, etc., XV, Syd. 70, l. 17-25; Op. Omn. 71, l. 22-29.

[121] Harvey: On the Motion, etc., XVI, Syd. 72, l. 8-11; Op. Omn. 73, l. 13-16.

[122] Harvey: On the Motion, etc., XVII, Syd. 83, l. 9-27; Op. Omn. 84, l. 31 to 85, l. 14.

[123] Hippocrates: On the Nature of the Child, Lit. Vol. VII, 530, l. 3-19.

[124] Aristotle: History of Animals, 561_a_, 4 to 562_b_, 2.

[125] Harvey: On the Motion, etc., XVII, Syd. 76, l. 3-10; Op. Omn. 77, l. 14-20. On Generation, XVII, Syd. 235, l. 21-26; Op. Omn. 249, l. 9-13.

[126] Harvey: On the Motion, etc., IV, Syd. 30, l. 14-18 and 30, l. 31 to 31, l. 4; Op. Omn. 32, l. 8-10 and 32, l. 22-30.

[127] Aristotle: On the Parts of Animals, 666_a_, 8-13.

[128] _Principium._

[129] Harvey: On the Motion, etc., XVI, Syd. 74, l. 4-15; Op. Omn. 75, l. 9-19.

[130] It would be natural to conjecture that this Aristotelian slighting of spirits derived from the air, taken in connection with Aristotle's exaltation of the vital innate heat, may have had much weight with Harvey, who, although he used the word "spirits" freely, insisted that the blood and the spirits are one. But in this matter the Aristotelian precedent cannot have had the same force for Harvey that it would have for us, because he believed Aristotle to be the author of two treatises in which the spirits are expressly treated, not only as entities, but as entities of great physiological importance, though their relations with the outer air are neglected in one of the treatises and quite obscurely dealt with in the other. (See Harvey: On the Motion, etc., IV, Syd. 29, l. 16-25; Op. Omn. 31, l. 8-16. Do., VI, Syd. 38, l. 7-12; Op. Omn. 40, l. 2-5.) Indeed, Harvey in one of his references to Aristotle directly affirmed that the philosopher had believed in "motor spirits" within the animal body. (See Harvey: On the Motion, etc., XVII, Syd. 81, l. 8-12; Op. Omn. 82, l. 31 to 83, l. 3. Compare [Pseudo-] Aristotle: On Spirits, 485_a_, 5-8; and the Latin translation of the same "by an unknown interpreter," 249_b_, 13-18.) The two treatises in question are entitled, respectively, "On the Motion of Animals" and "On Spirits," and have been attributed to Aristotle and habitually printed among his works, both before and since the time of Harvey. Modern criticism, however, has made it clear that neither treatise is a genuine work of Aristotle. It is especially plain that the treatise "On Spirits" is by another hand and of another school; among other reasons, because the author declares the skin to be supplied with blood by the veins, and with spirits by accompanying vessels which he calls "arteries." In this treatise the maintenance of the spirits by respiration is discussed, but left uncertain (483_b_, 15-19). It is but fair to the criticism of Harvey's time to note that, glaringly at variance as the undoubted works of Aristotle are with the treatise "On Spirits," the latter was pronounced genuine, in 1839, by so eminent a scholar as É. Littré, in his "Œuvres d'Hippocrate," etc., Vol. I, 203. Reasons why the treatises in question are not by Aristotle, are given at length in the essay in Latin by V. Rose, entitled "De Aristotelis Librorum Ordine et Auctoritate Commentatio," Berlin, 1854, 162-171, and at the end of 174.

[131] Compare the Iliad, Book XXI, 441.

[132] ἐν τούτῳ γὰρ ἡ φύσις ἐμπεπύρευκεν ἀυτήν. Aristotle: On Respiration, 474_b_, 10-13.

[133] Aristotle: On Youth and Old Age, etc., 469_a_, 11-12 and 17-20.

[134] Plato: Timæus, 70_a_-_b_ and 77_d_-_e_.

[135] κίνησις.

[136] νεῦρα.

[137] Aristotle: On the Parts of Animals, 666_b_, 11-16.

[138] Harvey: On the Motion, etc., XVII, Syd. 81, l. 12-19; Op. Omn. 83, l. 3-8.

[139] Harvey: On Generation, XI, Syd. 207, l. 33-35; Op. Omn. 220, l. 26-28.

[140] The foregoing statements and summaries of Aristotelian doctrine are based upon the following portions of Aristotle's works: Meteorology, 366_b_, 2 to 367_a_, 3. On Soul, 413_a_, 11 to 415_a_, 13; 416_a_, 9 to _b_, 31; 426_b_, 8 to 427_a_, 16; 429_a_, 10 to 430_a_, 9. The following five titles are of treatises among the Parva Naturalia: On Sensation and the Sensible, 438_b_, 24 to 439_a_, 5; On Sleep and Waking, 455_a_, 4 to 458_a_, 32; On Dreams, 461_b_, 11-15; On Youth and Old Age, and On Life and Death, the whole treatise; On Respiration, 473_a_, 9-10; 475_a_, 25 to _b_, 24; 478_a_, 11 to _b_, 21; 479_a_, 29 to _b_, 7; 479_b,_ 17 to 480_b_, 20. History of Animals, 496_a_, 4 to 497_b_, 2; 512_b_, 12 to 515_b_, 26; 535_a_, 26 to 536_a_, 4; 561_a_, 4 to 562_b_, 2. Of the History of Animals Book X is clearly spurious; see V. Rose: "De Aristotelis Librorum Ordine et Auctoritate Commentatio," 171-174.