The Works of William Harvey

The Works of William Harvey

Translated by Robert Willis
Introduction by Arthur C. Guyton
Copyright Date: 1989
Pages: 736
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  • Book Info
    The Works of William Harvey
    Book Description:

    William Harvey's revolutionary book on the circulatory system, published in Latin in 1628, demonstrated for the first time how the heart pumps blood through the body. His findings overturned the world's basic understanding of the way the body functions and changed fundamental knowledge of physiology as much as any scientific work in history. The Works of William Harvey will provide scientists, students, physicians, and interested lay persons access to the original works of a pioneer who shaped contemporary science.This edition is a reissue of the 1965 facsimile of the 1867 collection and translation of Harvey's works. Included are his groundbreaking 1628 book on the circulatory system, a book on animal reproduction, and various shorter scientific writings and letters, along with a new introduction.

    eISBN: 978-0-8122-0862-7
    Subjects: Health Sciences

Table of Contents

  1. Front Matter
    (pp. i-iv)
    (pp. 1-28)

    William Harvey’s book on the circulation, published in 1628, demonstrated clearly that the heart pumps blood in a circle through the body. Strange as it seems to us today, this concept was so revolutionary to Harvey’s contemporaries that the world’s basic understanding of how the body functions was thrown into turmoil. Only after another half century did the immediate aftershocks clear, leaving a legacy that affected forever all of medical science. This book, written in Latin, was entitledExercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus,and commonly referred to asde Motu Cordis.Its English translation isAnatomical...

    (pp. i-x)
  4. Table of Contents
    (pp. xi-xvi)
    (pp. xvii-lxxxviii)

    William Harvey, the immortal discoverer of the Circulation of the Blood, was the eldest son of Thomas Harvey and Joan Halke, of Folkstone, in Kent, where he was born on the 1st of April, 1578.¹ Of the parents of Harvey, little is known. His father, in our printed accounts, is generally designated Gentleman,² and must have been in easy circumstances; inasmuch as he had a numerous family, consisting of seven sons and two daughters, all the males of which he felt himself competent to launch upon life in courses that imply the possession of money wealth. William, the first-born, adopted...

  6. THE LAST WILL AND TESTAMENT OF WILLIAM HARVEY. M.D. Extracted from the Registry of the Prerogative Court of Canterbury.
    (pp. ixc-xcvi)
    William Harvey

    In the name of the Almighty and Eternal God Amen I William Harvey of London Doctor of Physicke doe by these presents make and ordaine this my last Will and testament in manner and forme following Revoking hereby all former and other wills and testaments whatsoever Imprimis I doe most humbly render my soule to Him that gave it and to my blessed Lord and Saviour Christ Jesus and my bodie to the Earth to be buried at the discretion of my executor herein after named The personall estate which at the time of rny decease I shalbe in any...

    • Dedication
      (pp. 3-8)

      I have already and repeatedly presented you, my learned friends, with my new views of the motion and function of the heart, in my anatomical lectures; but having now for nine years and more confirmed these views by multiplied demonstrations in your presence, illustrated them by arguments, and freed them from the objections of the most learned and skilful anatomists, I at length yield to the requests, I might say entreaties, of many, and here present them for general consideration in this treatise.

      Were not the work indeed presented through you, my learned friends, I should scarce hope that it...

      (pp. 9-19)

      As we are about to discuss the motion, action, and use of the heart and arteries, it is imperative on us first to state what has been thought of these things by others in their writings, and what has been held by the vulgar and by tradition, in order that what is true may be confirmed, and what is false set right by dissection, multiplied experience, and accurate observation.

      Almost all anatomists, physicians, and philosophers, up to the present time, have supposed, with Galen, that the object of the pulse was the same as that of respiration, and only differed...

      (pp. 19-20)

      When I first gave my mind to vivisections, as a means of discovering the motions and uses of the heart, and sought to discover these from actual inspection, and not from the writings of others, I found the task so truly arduous, so full of difficulties, that I was almost tempted to think, with Fracastorius, that the motion of the heart was only to be comprehended by God.

      For I could neither rightly perceive at first when the systole and when the diastole took place, nor when and where dilatation and contraction occurred, by reason of the rapidity of the...

      (pp. 21-23)

      In the first place, then, when the chest of a living animal is laid open and the capsule that immediately surrounds the heart is slit up or removed, the organ is seen now to move, now to be at rest;—there is a time when it moves, and a time when it is motionless.

      These things are more obvious in the colder animals, such as toads, frogs, serpents, small fishes, crabs, shrimps, snails and shell-fish. They also become more distinct in warm-blooded animals, such as the dog and hog, if they be attentively noted when the heart begins to flag,...

      (pp. 24-26)

      In connexion with the motions of the heart these things are further to be observed having reference to the motions and pulses of the arteries:

      1. At the moment the heart contracts, and when the breast is struck, when in short the organ is in its state of systole, the arteries are dilated, yield a pulse, and are in the state of diastole. In like manner, when the right ventricle contracts and propels its charge of blood, the arterial vein [the pulmonary artery] is distended at the same time with the other arteries of the body.

      2. When the left...

      (pp. 26-31)

      Besides the motions already spoken of, we have still to consider those that appertain to the auricles.

      Caspar Bauhin and John Riolan,¹ most learned men and skilful anatomists, inform us from their observations, that if we carefully watch the movements of the heart in the vivisection of an animal, we shall perceive four motions distinct in time and in place, two of which are proper to the auricles, two to the ventricles. With all deference to such authority I say, that there are four motions distinct in point of place, but not of time; for the two auricles move together,...

      (pp. 31-34)

      From these and other observations of the like kind, I am persuaded it will be found that the motion of the heart is as follows:

      First of all, the auricle contracts, and in the course of its contraction throws the blood, (which it contains in ample quantity as the head of the veins, the store-house and cistern of the blood,) into the ventricle, which being filled, the heart raises itself straightway, makes all its fibres tense, contracts the ventricles, and performs a beat, by which beat it immediately sends the blood supplied to it by the auricle into the arteries;...

      (pp. 35-40)

      Since the intimate connexion of the heart with the lungs, which is apparent in the human subject, has been the probable cause of the errors that have been committed on this point, they plainly do amiss who, pretending to speak of the parts of animals generally, as anatomists for the most part do, confine their researches to the human body alone, and that when it is dead. They obviously act no otherwise than he who, having studied the forms of a single commonwealth, should set about the composition of a general system of polity; or who, having taken cognizance of...

      (pp. 40-45)

      That this is possible, and that there is nothing to prevent it from being so, appears when we reflect on the way in which water percolating the earth produces springs and rivulets, or when we speculate on the means by which the sweat passes through the skin, or the urine through the parenchyma of the kidneys. It is well known that persons who use the Spa waters, or those of La Madonna, in the territories of Padua, or others of an acidulous or vitriolated nature, or who simply swallow drinks by the gallon, pass all off again within an hour...

      (pp. 45-47)

      Thus far I have spoken of the passage of the blood from the veins into the arteries, and of the manner in which it is transmitted and distributed by the action of the heart; points to which some, moved either by the authority of Galen or Columbus, or the reasonings of others, will give in their adhesion. But what remains to be said upon the quantity and source of the blood which thus passes, is of so novel and unheard-of character, that I not only fear injury to myself from the envy of a few, but I tremble lest I...

      (pp. 48-52)

      But lest any one should say that we give them words only, and make mere specious assertions without any foundation, and desire to innovate without sufficient cause, three points present themselves for confirmation, which being stated, I conceive that the truth I contend for will follow necessarily, and appear as a thing obvious to all. First,—the blood is incessantly transmitted by the action of the heart from the vena cava to the arteries in such quantity, that it cannot be supplied from the ingesta, and in such wise that the whole mass must very quickly pass through the organ;...

      (pp. 52-54)

      So far our first position is confirmed, whether the thing be referred to calculation or to experiment and dissection, viz., that the blood is incessantly infused into the arteries in larger quantities than it can be supplied by the food; so that the whole passing over in a short space of time, it is matter of necessity that the blood perform a circuit, that it return to whence it set out.

      But if any one shall here object that a large quantity may pass through and yet no necessity be found for a circulation, that all may come from the...

      (pp. 54-60)

      That this may the more clearly appear to every one, I have here to cite certain experiments, from which it seems obvious that the blood enters a limb by the arteries, and returns from it by the veins; that the arteries are the vessels carrying the blood from the heart, and the veins the returning channels of the blood to the heart; that in the limbs and extreme parts of the body the blood passes either immediately by anastomosis from the arteries into the veins, or mediately by the pores of the flesh, or in both ways, as has already...

      (pp. 60-62)

      If these things be so, another point which I have already referred to, viz., the continual passage of the blood through the heart will also be confirmed. We have seen, that the blood passes from the arteries into the veins, not from the veins into the arteries; we have seen, farther, that almost the whole of the blood may be withdrawn from a puncture made in one of the cutaneous veins of the arm if a bandage properly applied be used; we have seen, still farther, that the blood flows so freely and rapidly that not only is the whole...

      (pp. 62-67)

      Thus far have we spoken of the quantity of blood passing through the heart and the lungs in the centre of the body, and in like manner from the arteries into the veins in the peripheral parts and the body at large. We have yet to explain, however, in what manner the blood finds its way back to the heart from the extremities by the veins, and how and in what way these are the only vessels that convey the blood from the external to the central parts; which done, I conceive that the three fundamental propositions laid down for...

      (pp. 68-68)

      And now I may be allowed to give in brief my view of the circulation of the blood, and to propose it for general adoption.

      Since all things, both argument and ocular demonstration, show that the blood passes through the lungs and heart by the action of the [auricles and] ventricles, and is sent for distribution to all parts of the body, where it makes its way into the veins and pores of the flesh, and then flows by the veins from the circumference on every side to the centre, from the lesser to greater veins, and is by them...

      (pp. 68-71)

      It will not be foreign to the subject if I here show further, from certain familiar reasonings, that the circulation is matter both of convenience and necessity. In the first place, since death is a corruption which takes place through deficiency of heat,¹ and since all living things are warm, all dying things cold, there must be a particular seat and fountain, a kind of home and hearth, where the cherisher of nature, the original of the native fire, is stored and preserved; whence heat and life are dispensed to all parts as from a fountain head; whence sustenance may...

      (pp. 71-75)

      There are still certain phenomena, which, taken as consequences of this truth assumed as proven, are not without their use in exciting belief, as it were,a posteriore;and which, although they may seem to be involved in much doubt and obscurity, nevertheless readily admit of having reasons and causes assigned for them. The phenomena alluded to are those that present themselves in connexion with contagions, poisoned wounds, the bites of serpents and rabid animals, lues venerea and the like. We sometimes see the whole system contaminated, though the part first infected remains sound; the lues venerea has occasionally made...

      (pp. 75-86)

      I do not find the heart as a distinct and separate part in all animals; some, indeed, such as the zoophytes, have no heart; this is because these animals are coldest, of no great bulk, of soft texture or of a certain uniform sameness or simplicity of structure; among the number I may instance grubs and earthworms, and those that are engendered of putrefaction and do not preserve their species. These have no heart, as not requiring any impeller of nourishment into the extreme parts; for they have bodies which are connate and homogeneous, and without limbs; so that by...

      (pp. 89-106)
      William Harvey

      Some few months ago there appeared a small anatomical and pathological work from the pen of the celebrated Riolanus, for which, as sent to me by the author himself, I return him my grateful thanks.¹ I also congratulate this author on the highly laudable undertaking in which he has engaged. To demonstrate the seats of all diseases is a task that can only be achieved under favour of the highest abilities; for surely he enters on a difficult province who proposes to bring under the cognizance of the eyes those diseases which almost escape the keenest understanding. But such efforts...

      (pp. 109-142)

      It is now many years, most learned Riolanus, since, with the aid of the press, I published a portion of my work. But scarce a day, scarce an hour, has passed since the birth-day of the Circulation of the blood, that I have not heard something for good or for evil said of this my discovery. Some abuse it as a feeble infant, and yet unworthy to have seen the light; others, again, think the bantling deserves to be cherished and cared for; these oppose it with much ado, those patronise it with abundant commendation; one party holds that I...

    • Dedication
      (pp. 145-150)

      Harassed with anxious, and in the end not much availing cares, about Christmas last,¹ I sought to rid my spirit of the honour and ornament of our College, Dr. William Harvey, then dwelling not far from the city. I found him, Democritus like, busy with the study of natural things, his countenance cheerful, his mind serene, embracing all within its sphere. I forthwith saluted him, and asked if all were well with him? “How can it,” said he, “whilst the Commonwealth is full of distractions, and I myself am still in the open sea? And truly,” he continued, “did I...

      (pp. 151-168)

      It will not, I trust, be unwelcome to you, candid reader, if I yield to the wishes, I might even say the entreaties, of many, and in these Exercises on Animal Generation, lay before the student and lover of truth what I have observed on this subject from anatomical dissections, which turns out to be very different from anything that is delivered by authors, whether philosophers or physicians.

      Physicians, following Galen, teach that from the semen of the male and female mingled in coition the offspring is produced, and resembles one or other, according to thepredominanceof this one...

      • EXERCISE THE FIRST. Wherefore we begin with the history of the hen’s egg.
        (pp. 169-171)

        Hieronymus Fabricius of Aquapendente, (whom, as I have said, I have chosen my informant of the way I am to follow,) in the beginning of his book on the Formation of the Ovum and Chick, has these words: “My purpose is to treat of the formation of the foetus in every animal, setting out from that which proceeds from the egg: for this ought to take precedence of all discussion of the subject, both because from this it is not difficult to make out Aristotle’s views of the matter, and because his treatise on the Formation of the Foetus from...

      • EXERCISE THE SECOND. Of the seat of generation.
        (pp. 171-172)

        “Nature,” says Fabricius, “was first solicitous about the place [where generation should proceed], which she determined should be either within or without the animal: within she ordained the uterus; without, the ovum: in the uterus the blood and seminal fluid engendering; in the ovum, however, the fluids or elements of which it consists supplying pabulum for the production of the foetus.”

        Now, whatever is procreated of the semen properly so called originates and is perfected either in the same place or in different places. All viviparous creatures derive their origin and have their completion in the uterus itself; but oviparous...

      • EXERCISE THE THIRD. Of the upper part of the hen’s uterus, or the ovary.
        (pp. 172-179)

        The uterus of the fowl is divided by Fabricius into the superior and inferior portions, and the superior portion he calls the ovary.

        The ovary is situated immediately beneath the liver, close to the spine, over the descending aorta. In this situation, in the larger animals with red blood, the coeliac artery enters the mesentery, at the origin, namely, of the emulgent veins, or a little lower; in the situation moreover in which in the other redblooded and viviparous animals the vasa praeparantia, tending to the testes, take their origin: in the same place at which the testes of the...

      • EXERCISE THE FOURTH. Of the infundibulum.
        (pp. 179-180)

        The next succeeding portion of the uterus of the common fowl is called the infundibulum by Fabricius. It forms a kind of funnel or tube, extending downwards from the ovary, (which it everywhere embraces,) and becoming gradually wider, terminates in the superior produced portion of the uterus. This infundibulum yields a passage to the yelks when they have broken from their foot-stalks in their descent from the ovary into the second uterus (so it is styled by Fabricius). It resembles the tunica vaginalis in the scrotum, and is a most delicate membrane, very easily dilatable, fitted to receive the yelks...

      • EXERCISE THE FIFTH. Of the external portion of the uterus of the common fowl.
        (pp. 180-190)

        Fabricius pursues his account of the uterus after having described the ovary, and in such an inverse order, that he premises a description of the superior portion or appendage of the uterus before he approaches the uterus itself. He assigns to it three turns or spirals, with somewhat too much of precision or determinateness, and settles the respective situations of these spirals, which are nevertheless of uncertain seat. Here, too, he very unnecessarily repeats his definition of the infundibulum. would, therefore, in this place, beg to be allowed to give my own account of the uterus of the fowl, according...

      • EXERCISE THE SIXTH. Of the uterus of the fowl.
        (pp. 190-195)

        The passage from the external uterine orifice to the internal parts and uterus itself, where the egg is perfected, is by that part which in other animals is called the vagina or vulva. In the fowl, however, this passage is so intricate, and its internal membrane is so loose and wrinkled, that although there is a ready passage from within outwards, and a large egg makes its way through all without much difficulty, still it scarcely seems likely that the penis of the male could penetrate or the spermatic fluid make its way through it; for I have found it...

      • EXERCISE THE SEVENTH. Of the abdomen of the common fowl and of other birds.
        (pp. 195-198)

        From the external orifice proceeding through the vulva we come to the uterus of the fowl, in which the egg is perfected, surrounded with the white and covered with its shell. But before speaking of the situation and connections of this part it seems necessary to premise a few words on the particular anatomy of the abdomen of birds. For I have observed that the stomach, intestines, and other viscera of the feathered kinds were otherwise placed in the abdomen, and differently constituted, than they are in quadrupeds.

        Almost all birds are provided with a double stomach ; one of...

      • EXERCISE THE EIGHTH. Of the situation and structure of the remaining parts of the fowl’s uterus.
        (pp. 198-201)

        Between the stomach and the liver, over the spine, and where, in man and other animals the pancreas is situated; between the trunk of the porta and the descending cava; at the origin of the renal and spermatic arteries, and where the cæliac artery plunges into the mesentery, there, in the fowl and other birds, do the ovary and the cluster of yelks present themselves; having in their front the trunk of the porta, the gullet, and the orifice of the stomach: behind them, the vena cava and the aorta descending along the spine; above the liver, and beneath the...

      • EXERCISE THE NINTH. Of the extrusion of the egg, or parturition of the fowl, in general.
        (pp. 201-202)

        The yelk, although only a minute speck in the ovary, gaining by degrees in depth of colour and increasing in size, gradually acquires the dimensions and characters that distinguish it at last. Cast loose from the cluster, it descends by the infundibulum, and, transmitted through the spirals and cells of the processus uteri, it becomes surrounded with albumen; and this, without in any place adhering to the uterus (as was rightly observed by Fabricius in opposition to Aristotle), or growing by means of any system of umbilical vessels; but as the eggs of fishes and frogs, when extruded and laid...

      • EXERCISE THE TENTH. Of the increase and nutrition of the egg.
        (pp. 202-204)

        Let us hear Fabricius on these topics. He says: “As the action of the stomach is to prepare the chyle, and that of the testes to secrete the seminal fluid, (because in the stomach chyle is discovered, and in the testes semen,) so we declare the act of the uterus in birds to be the production of eggs, because eggs are found there. But this, as it appears, is not the only action of uteri; to it must be added the increase of the egg, which succeeds immediately upon its production, and which proceeds until it is perfected and attains...

      • EXERCISE THE ELEVENTH. Of the covering or shell of the egg.
        (pp. 204-211)

        It will now be proper, having spoken of the production of eggs, to treat of their parts and diversities. “An egg,” says Fabricius, “consists of a yelk, the albumen, two chalazæ, three membranes, viz. one proper to the vitellus, two common to the entire egg, and a shell. To these two others are to be added, which, however, cannot be correctly reckoned among the parts of an egg; one of these is a small cavity in the blunt end of the egg, under the shell; the other is a very small white spot, a kind of round cicatricula connected with...

      • EXERCISE THE TWELFTH. Of the remaining parts of the egg.
        (pp. 211-215)

        We have already spoken partially of the place where, the time when, and the manner how the remaining parts of the egg are engendered, and we shall have something more to add when we come to speak of their several uses.

        “The albumen,” says Fabricius,¹ “is theovi albus liquorof Pliny, theovi candidumof Celsus, theovi alborof Palladius, theovi album et albumentumof Apicius, the λευκòν of the Greeks, the ώοṽ λεύκωμα of Aristotle, the ονιθος yáλα, or bird’s milk of Anaxagoras. This is the cold, sluggish, white fluid of the egg, of different thickness...

      • EXERCISE THE THIRTEENTH. Of the diversities of eggs.
        (pp. 216-225)

        “The word ovum, or egg, is taken in a twofold sense, proper and improper. An ovum, properly so designated, I call that body to which the definition given by Aristotle¹ applies: An egg, says he, is that from part of which an animal is engendered, and the remainder of which is food for the animal so produced. But I hold that body to be improperly styled an egg which is defined by Aristotle² in the same place, to be that from the whole of which an animal is engendered; such as the eggs of ants, flies, spiders, some butterflies, and...

      • EXERCISE THE FOURTEENTH. Of the production of the chick from the egg of the hen.
        (pp. 225-228)

        Of the growth and generation of the hen’s egg enough has already been said; and we have now to lay before the reader our observations on the procreation of the chick from the egg,—a duty which is equally difficult, and profitable, and pleasant. For in general the first processes of nature lie hid, as it were, in the depths of night, and by reason of their subtlety escape the keenest reason no less than the most piercing eye.

        Nor in truth is it a much less arduous business to investigate the intimate mysteries and obscure beginnings of generation than...

      • EXERCISE THE FIFTEENTH. The first examination of the egg; or of the effect of the first day’s incubation upon the egg.
        (pp. 228-231)

        That we may be the more clearly informed of the effect which the first day’s incubation produces upon the egg, we must set out by ascertaining what changes take place in an egg spontaneously, changes that distinguish a stale egg from one that is new-laid, when what is due to the incubationper sewill first be clearly apprehended.

        The space or cavity in the blunt end is present, as we have said, in every egg; but the staler the egg the larger does this hollow continually grow; and this is more especially the case when eggs are kept in...

      • EXERCISE THE SIXTEENTH. Second inspection of the egg.
        (pp. 232-234)

        The second day gone by, the circles of the cicatricula that have been mentioned, have become larger and more conspicuous, and may now be of the size of the nail of the ring-finger, sometimes even of that of the middle finger. By these rings the whole cicatricula is indistinctly divided into two, occasionally into three regions, which are frequently of different colours, and bear a strong resemblance to the cornea of the eye, both as respects dimensions, a certain degree of prominence, and the presence of a transparent and limpid fluid included within it. The centre of the cicatricula here...

      • EXERCISE THE SEVENTEENTH. The third inspection of the egg.
        (pp. 234-243)

        Having seen the second process or preparation of the egg, towards the production of the embryo which presents itself in the course of the third day, we proceed to the Third Stage, which falls to be considered after the lapse of three days and as many nights. Aristotle¹ says: “Traces of generation commence in the egg of the hen after three days and three nights [of incubation];” for example, on Monday morning, if in the morning of the preceding Friday the egg has been put under the hen. This stage forms the subject of the third figure in Fabricius.


      • EXERCISE THE EIGHTEENTH. The fourth inspection of the egg.
        (pp. 243-251)

        “In the course of the fifth day of incubation,” says Aristotle,³ “the body of the chick is first distinguished, of very small dimensions indeed, and white; but the head conspicuous and the eyes extremely prominent, a state in which they afterwards continue long; for they only grow smaller and shrink at a later period. In the lower portion of the body there is no rudimentary member corresponding with what is seen in the upper part. But of the channels which proceed from the heart, one now tends to the investing membrane, the other to the yelk; together they supply the...

      • EXERCISE THE NINETEENTH. The fifth inspection of the egg.
        (pp. 252-255)

        On the sixth day the three cells of the head present themselves more distinctly, and the coats of the eyes are now apparent; the legs and the wings also bud forth, much in the way in which, towards the end of June, we see tadpoles getting their extremities, when they quit the water, and losing their tails assume the form of frogs.

        In the chick, the rump has still no other form than is conspicuous in animals at large, even in serpents; it is a round and slender tail. The substance of the heart now grows upon the pulsating vesicle;...

      • EXERCISE THE TWENTIETH. The sixth inspection.
        (pp. 256-257)

        Everything is still more distinct upon the seventh day, and the rudiments of several of the particular parts are now conspicuous, viz., the wings, legs, genital organs, divisions for the toes, thighs, ilia, &c. The embryo now moves and kicks, and the form of the perfect chick is recognizable; from this time forward, indeed, nothing is superadded; the very delicate parts only increase in size. The more the parts grow the more is the albumen consumed, and the external membranes united come to be of the nature of the secundines, and ever more and more closely represent the umbilical cord....

      • EXERCISE THE TWENTY-FIRST. The inspection after the tenth day.
        (pp. 257-259)

        All that presents itself on the tenth day is so accurately described by Aristotle that scarcely anything remains for us to add. Now his opinion, according to my interpretation of it, is this, viz., that “on the tenth day the entire chick is conspicuous,”¹ being pellucid and white in every part except the eyes and the venous ramifications. “The head at this time is larger than the whole of the rest of the body; and eyes larger than the head are connected with it,” (adhering, and being in some sort appended to the head,) “but having as yet no pupils,”...

      • EXERCISE THE TWENTY-SECOND. The inspection after the fourteenth day.
        (pp. 259-264)

        From the seventh to the fourteenth day everything has grown and become more conspicuous. The heart and all the other viscera have now become concealed within the abdomen of the embryo, and the parts that formerly were seen naked and projecting externally, can now only be perceived when the thorax and abdomen are laid open. The chick too now begins to be covered with feathers, the roots of which are first perceived as black points. The pupils of the eyes are distinguished; the eyelids appear, as does also the membrana nictitans in the greater canthus of the eye, a membane...

      • EXERCISE THE TWENTY-THIRD. Of the exclusion of the chick, or the birth from the egg.
        (pp. 264-267)

        The egg is, as we have said, a kind of exposed uterus, and place in which the embryo is fashioned: for it performs the office of the uterus and enfolds the chick until the due time of its exclusion arrives, when the creature is born perfect. Oviparous animals consequently are not distinguished from viviparous by the circumstance of the one bringing forth their young alive, and the other not doing so; for the chick not only lives and moves within the egg, but even breathes and chirps whilst there; and, when it escapes from the shell, enjoys a more perfect...

      • EXERCISE THE TWENTY-FOURTH. Of twin-bearing eggs.
        (pp. 268-269)

        Twin-bearing eggs are such as produce twin chickens, and according to Aristotle,¹ “are possessed of two yelks, which, in some are separated by a layer of thin albumen, that they may less encroach on one another; in others, however, there is nothing of the sort, and then the two yelks are in contact.”

        I have frequently seen twin eggs, each of the yelks in which was surrounded by an albumen, with common and proper membranes surrounding them. I have also met with eggs having two yelks connate, as it were, both of which were embraced by a single and common...

      • EXERCISE THE TWENTY-FIFTH. Certain Deductions from the preceding History of the Egg.
        (pp. 270-270)

        Such is the history of the hen’s egg; in which we have spoken of its production, and of its action or faculty to engender a chick, at too great length, it may appear to those who do not see the end and object of such painstaking, of such careful observation. Wherefore I think it advisable here to state what fruits may follow our industry, and in the words of the learned Lord Verulam, to “enter upon our second vintage.” Certain theorems, therefore, will have to be gathered from the history given; some of which will be quite certain, some questionable...

      • EXERCISE THE TWENTY-SIXTH. Of the nature of the egg.
        (pp. 270-279)

        Of the theorems that refer to the egg, some teach us what it is, some show its mode of formation, and others tell of the parts which compose it.

        It is certain, in the first place, that one egg produces one chick only. Although the egg be in a certain sense an external uterus, still it most rarely engenders several embryos, but by far the most frequently produces no more than a single pullet. And when an egg produces two chicks, which it does sometimes, still is this egg to be reputed not single but double, and as possessed of...

      • EXERCISE THE TWENTY-SEVENTH. The egg is not the product of the uterus, but of the vital principle.
        (pp. 279-284)

        “As we have said,” says Fabricius,¹ “that the action of the stomach was to convert the food into chyle, and the action of the testicles to produce semen, because in the stomach we find chyle, in the testes semen, so do we definitely assert that the egg is the product of the uterus of birds, because it is found in this part. The organ and seat of the generation of eggs is, therefore, intimately known and obvious to us. And farther, inasmuch as there are two uteri in birds, one superior and the other inferior, and these are considerably different...

      • EXERCISE THE TWENTY-EIGHTH. The egg is not produced without the hen.
        (pp. 284-287)

        Leaving points that are doubtful, and disquisitions bearing upon the general question, we now approach more definite and obvious matters.

        And first, it is manifest that a fruitful egg cannot be produced without the concurrence of a cock and hen: without the hen no egg can be formed; without the cock it cannot become fruitful. But this view is opposed to the opinion of those who derive the origin of animals from the slime of the ground. And truly when we see that the numerous parts concurring in the act of generation,—the testes and vasa deferentia in the male,...

      • EXERCISE THE TWENTY-NINTH. Of the manner, according to Aristotle, in which a perfect and fruitful egg is produced by the male and female fowl.
        (pp. 287-291)

        Shortly before we said that a fruitful egg is not engendered spontaneously, that it is not produced save by a hen, and by her only through the concurrence of the cock. This agrees with the matter of the following sentence of Aristotle:¹ “The principles of generation have particular reference to male and female; the male as supplying the original of motion and reproduction; the female as furnishing the matter.”

        In our view, however, an egg is a true generative seed, analogous to the seed of a plant; the original conception arising between the two parents, and being the mixed fruit...

      • EXERCISE THE THIRTIETH. Of the uses of this disquisition on fecundity.
        (pp. 291-293)

        This disquisition on the inherent qualities of the egg and the cause of its fecundity, is alike in point of difficulty and subtlety, but of the highest importance. For it was imperative on us to inquire what there was in the conception, what in the semen masculinum, and what in the female fowl, which render these fertile; and what there is in the fruitful cock which makes him differ from a bird that is barren. Is the cause identical with that which we have called the vital principle (anima) in the embryo, or it is a certain portion of the...

      • EXERCISE THE THIRTY-FIRST. The egg is not produced by the cock and hen in the way Aristotle would have it.
        (pp. 293-294)

        It is certain, as we have said, that a fruitful egg is not produced without the concurrence of the cock and hen; but this is not done in the way that Aristotle thought, viz. by the cock as prime and sole ‘agent,’ the hen only furnishing the ‘matter.’ Neither do I agree with him when he says:¹ “When the semen masculinum enters the female uterus, it coagulates the purest portion of the catamenia;” and shortly afterwards: “but when the catamenia of the female has set in the uterus, it forms, with the semen masculinum, a coagulum like that of milk;...

      • EXERCISE THE THIRTY-SECOND. Nor in the manner imagined by physicians.
        (pp. 294-295)

        Conception, according to the opinion of medical men, takes place in the following way: during intercourse the male and female dissolve in one voluptuous sensation, and eject their seminal fluids (genituræ) into the cavity of the uterus, where that which each contributes is mingled with that which the other supplies, the mixture having from both equally the faculty of action and the force of matter; and according to the predominance of this or of that geniture does the progeny turn out male or female. It is farther imagined that immediately after the intercourse, the active and passive principles cooperating, something...

      • EXERCISE THE THIRTY-THIRD. The male and the female are alike efficient in the business of generation.
        (pp. 296-297)

        The medical writers with propriety maintain, in opposition to the Aristotelians, that both sexes have the power of acting as efficient causes in the business of generation; inasmuch as the being engendered is a mixture of the two which engender: both form and likeness of body, and species are mixed, as we see in the hybrid between the partridge and common fowl. And it does indeed seem consonant with reason to hold that they are the efficient causes of conception whose mixture appears in the thing produced.

        Aristotle entertaining this opinion says:¹ “In some animals it is manifest that such...

      • EXERCISE THE THIRTY-FOURTH. Of the matter of the egg, in opposition to the Aristotelians and the medical writers.
        (pp. 297-300)

        The position taken up by the medical writers against the Aristotelians, viz., that the blood is not the first element in a conception, is clearly shown from the generation of the egg to be well chosen : neither during intercourse, nor before nor after it, is there a drop of blood contained in the uterus of the fowl; neither are the rudiments of eggs red, but white. Many animals also conceive in whose uteri, if they be suddenly laid open after intercourse, no blood can be demonstrated.

        But when they contend that the maternal blood is the food of the...

      • EXERCISE THE THIRTY-FIFTH. In how far is the fowl efficient in the generation of the egg, according to Aristotle? And wherefore is the concurrence of the male required?
        (pp. 300-302)

        It has been already stated that the cock and hen are the two principles in the generation of the egg, although of the manner in which they are so I am of a different opinion from Aristotle and medical authorities. From the production of the egg we have clearly shown that the female as well as the male was efficient, and that she had within her a principle whence motion and the faculty of forming flowed; although in the sexual act the male neither confers the matter, nor does the female eject any semen whence the egg is constituted. It...

      • EXERCISE THE THIRTY-SIXTH. The perfect hen’s egg is of two colours.
        (pp. 303-305)

        Every egg, then, is not perfect; but some are to be held imperfect because they have not yet attained their true dimensions, which they only receive when extruded; others are imperfect because they are yet unprolific, and only acquire a fertilizing faculty from without, such are the eggs of fishes. Other eggs again are held imperfect by Aristotle, because they are of one colour only, inasmuch as perfect eggs consist of yelk and albumen, and are of two colours, as if better concocted, more distinct in their parts, endowed with higher heat. The eggs that are called centenine or hundredth...

      • EXERCISE THE THIRTY-SEVENTH. Of the manner in which the egg is increased by the albumen.
        (pp. 305-307)

        From the history it appears that the rudiments of the eggs in the ovary are of very small size, mere specks, smaller than millet seeds, white and replete with watery fluid: these specks, however, by and by, become yelks, and then surround themselves with albumen.

        Aristotle seems to think that the albumen is generated in the way of secretion from the vitellus. It may be well to add his words:¹ “The sex,” he says, “is not the cause of the double colour, as if the white were derived from the male, the yellow from the female; both are furnished by...

      • EXERCISE THE THIRTY-EIGHTH. Of what the cock and hen severally contribute to the production of the egg.
        (pp. 307-309)

        Both cock and hen are to be reputed parents of the chick; for both are necessary principles of an egg, and we have proved both to be alike its efficient: the hen fashions the egg, the cock makes it fertile. Both, consequently, are instruments of the plastic virtue by which this species of animal is perpetuated.

        But as in some species there appears to be no occasion for males, females sufficing of themselves to continue the kind; so do we discover no males among these, but females only, containing the fertile rudiments of eggs in their interior; in other species,...

      • EXERCISE THE THIRTY-NINTH. Of the cock and the particulars most remarkable in his constitution.
        (pp. 309-312)

        The cock, as stated, is the prime efficient of the perfect or fruitful hen’s egg, and the chief cause of generation: without the male no chick would ever be produced from an egg, and in many ovipara not even would any egg be produced. It is, therefore, imperative on us that we look narrowly into his offices and uses, and inquire particularly what he contributes to the egg and chick, both in the act of intercourse and at other times.

        It is certain that the cock in coition emits his ‘geniture,’ commonly called semen, from his sexual parts, although he...

      • EXERCISE THE FORTIETH. Of the hen.
        (pp. 313-318)

        There are two instruments and two first causes of generation, the male and the female—for to the hen seems to belong the formation of the egg, as to the cock the fertilizing principle. In the act of intercourse, then, of these two, that which renders the egg fruitful is either transmitted from the male to the female, or by means of coition is generated in the hen. The nature of this principle, however, is no less difficult to ascertain than are the particulars of its communication, whether, for instance, we suppose such communication to take place with the whole...

      • EXERCISE THE FORTY-FIRST. Of the sense in which the hen may be called the “prime efficient:” and of her parturition.
        (pp. 318-322)

        It has already been said, that the hen is the efficient cause of generation, or an instrument of Nature in this work, not indeed immediately, or of herself; but when rendered prolific by commission from, and in virtue of the male. But as the male is considered by Aristotle to be the first principle of generation on his own merits, because the first impulse toward generation proceeds from him, so may the hen in some measure be put down as the first cause of generation ; inasmuch as the male is undoubtedly inflamed to venery by the presence of the...

      • EXERCISE THE FORTY-SECOND. Of the manner in which the generation of the chick takes place from the egg.
        (pp. 323-324)

        Hitherto we have considered the egg as the fruit and end; it still remains for us to treat of it as the seed and beginning. “We must now inquire” says Fabricius¹, “how the generation of the chick results from the egg, setting out from that principle of Aristotle and Galen, which is, even conceded by all., to wit, that all things which are made in this life, are manifestly made by these three: workers, instruments, and matter.

        But since in natural phenomena, the work is not extrinsic, but is included in the matter, or the instruments, he concludes that we...

      • EXERCISE THE FORTY-THIRD. In how many ways the chick may be said to be formed from the egg.
        (pp. 325-327)

        It is admitted, then, that the fœtus is formed from a prolific egg, as out of the proper matter, and as it were by the requisite agency, and that the same egg stands for both causes of the chick. For inasmuch as it derives its origin from the hen, and is considered as a fruit, it is the matter : but, in so far as it contains in its whole structure the prolific and plastic faculty infused by the male, it is called the efficient cause of the chick.

        Moreover, not only as Fabricius supposed, are these, namely, the agent...

      • EXERCISE THE FORTY-FOURTH. Fabricius is mistaken with regard to the matter of the generation of the chick in ovo.
        (pp. 327-333)

        As I proposed to myself at the outset, I continue to follow Fabricius as pointing out the way; and we shall, therefore, consider the three things which he says are to be particularly regarded in the generation of the chick, viz.: the agent, the matter, and the nourishment of the embryo. These must needs be all contained in the egg; he proposes various doubts or questions, and quotes the opinions of the most weighty authorities in regard to them, these opinions being frequently discordant. The first difficulty is in reference to the matter and nourishment of the chick. Hippocrates,¹ Anaxagoras,...

      • EXERCISE THE FORTY-FIFTH. What is the material of the chick, and how it is formed in the egg?
        (pp. 333-340)

        Since, then, we are of opinion, that for the acquisition of truth, we cannot rely on the theories of others, whether these rest on mere assertions, or even may have been confirmed by plausible arguments, except there be added thereto a diligent course of observation; we propose to show, by clearly-arranged remarks derived from the book of nature, what is the material of the fœtus, and in what manner it thence takes its origin. We have seen that one thing is made out of another (tanquam ex materia) in two ways, and this as well in works of art, as...

      • EXERCISE THE FORTY-SIXTH. Of the efficient cause of the generation of the chick and fœtus.
        (pp. 340-344)

        We have thus far spoken of the matter from which the chick in ovo is generated. We have still with Fabricius to say a few words on the efficient cause of the chick. As this subject is surrounded with difficulties, however; as writers nowhere else dispute more virulently or more wordily, and Aristotle himself in explaining the matter is singularly intricate and perplexed, and as various questions that can by no means be lightly treated do in fact present themselves for consideration, I conceive that I shall be undertaking a task worthy of the toil if, as I have done...

      • EXERCISE THE FORTY-SEVENTH. Of the manner in which the efficient cause of the chick acts, according to Aristotle.
        (pp. 344-350)

        It is universally allowed, that the male is the primary efficient cause in generation, on the ground that in him the species or form resides; and it is further affirmed, that the emission of his ‘geniture’ during coition, is the cause both of the existence and the fertility of the egg. But none of the philosophers nor physicians, ancient or modern, have sufficiently explained in what manner the seed of the cock produced a chick from the egg; nor have they solved the question proposed by Aristotle. Nor, indeed, is Aristotle himself much more explanatory, when he says, “that the...

      • EXERCISE THE FORTY-EIGHTH. The opinion of Fabricius on the efficient cause of the chick is refuted.
        (pp. 350-354)

        As I have chosen Aristotle, the most eminent among the ancient philosophers, and Fabricius of Aquapendente, one of the foremost anatomists of modern times, as my especial guides and sources of information on the subject of animal generation, when I find that I can make nothing of Aristotle upon a particular topic, I straightway turn to Fabricius; and now I desire to know what he thought of the efficient cause of generation.

        I find that he endeavours to satisfy three doubts or difficulties involved in this subject: First, What is the ‘efficient’ of the chick? This he answers, by saying,...

      • EXERCISE THE FORTY-NINTH. The inquiry into the efficient cause of the chick is one of great difficulty.
        (pp. 355-360)

        The discussion of the efficient cause of the chick is, as we have said, sufficiently difficult, and all the more in consequence of the various titles by which it has been designated. Aristotle, indeed, recites several efficient causes of animals, and numerous controversies have arisen on the subject among writers, (these having been particularly hot between medical authors and Aristotelians,) who have come into the arena with various explanations, both of the nature of the efficient cause and of the mode of its operation.

        And indeed the Omnipotent Creator is nowhere more conspicuous in his works, nowhere is his divinity...

      • EXERCISE THE FIFTIETH. Of the efficient cause of animals, and its conditions.
        (pp. 360-372)

        That we may proceed in our subject, therefore, and penetrate so far into the knowledge of the efficient cause of animal generation as seems needful in this place, we must begin by observing what instruments or media are devoted to it. And here we come at once to the distinction into male and female; seminal fluid and ovum, and its primordium. For some males, as well as some females, are barren, or but little prolific; and the seed of the male is at one time more, at another time less prolific; because the semen masculinum stored up in the vesiculæ...

      • EXERCISE THE FIFTY-FIRST. Of the order of generation; and, first, of the primary genital particle.
        (pp. 372-379)

        It will be our business, by and by, when we come to treat of the matter in especial, to show what happens to the female from a fruitful embrace; what it is that remains with her after this, and which we have still spoken of under the name of contagion, by which, as by a kind of infection, she conceives, and an embryo subsequently begins to grow of its own accord. Meantime, we shall discourse of those things that manifestly appear in connexion with the organs of generation which seem most worthy of particular comment.

        And first, since it appears...

      • EXERCISE THE FIFTY-SECOND. Of the blood as prime element in the body.
        (pp. 379-391)

        It is unquestionable, then, and obvious to sense, that the blood is the first formed, and therefore the genital part of the embryo, and that it has all the attributes which have been ascribed to it in the preceding exercise. It is both the author and preserver of the body; it is the principal element moreover, and that in which the vital principle (anima) has its dwelling-place. Because, as already said, before there is any particle of the body obvious to sight, the blood is already extant, has already increased in quantity, “and palpitates within the veins,” as Aristotle expresses...

      • EXERCISE THE FIFTY-THIRD. Of the inferences deducible from the course of the umbilical vessels in the egg.
        (pp. 392-397)

        We find the blood formed in the egg and embryo before any other part; and almost at the same moment appear its receptacles, the veins and the vesicula pulsans. Wherefore, if we regard the punctum saliens as the heart, and this along with the blood and the veins as constituting one and the same organ, conspicuous in the very commencement of the embryo, although we should admit that the proper substance of the heart was deposited subsequently, still we should be ready to admit with Aristotle that the heart (an organ made up of ventricles, auricles, vessels, and blood) was...

      • EXERCISE THE FIFTY-FOURTH. Of the order of the parts in Generation from an egg, according to Fabricius.
        (pp. 397-406)

        Having already determined what part is to be esteemed the first, the blood, to wit, with its receptacles, the heart, veins, and arteries, the next thing we have to do is to speak of the rest of the parts of the body and of the order and manner of their generation.

        Fabricius, in whose footsteps we have resolved to tread, in speaking of the generation of the chick in ovo, passes in review the actions which take place in the egg, and by the effect of which the parts are produced, discussing themseriatim,as if a clearer view were...

      • EXERCISE THE FIFTY-FIFTH. Of the order of the parts according to Aristotle.
        (pp. 407-414)

        The following appear to be Aristotle’s views of the order of generation:¹ “When conception takes place, the germ comports itself like a seed sown in the ground. For seeds likewise contain a first principle, which, existing in the beginning in potentia, by and by when it manifests itself, sends forth a stem and a root, by which aliment is taken up; for increase is indispensable. And so in a conception, in which all the parts of the body inhere in potentia, and the first principle exists in a state of special activity.”

        This principle in the egg—the body analogous...

      • EXERCISE THE FIFTY-SIXTH. Of the order of the parts in generation as it appears from observation.
        (pp. 414-426)

        That we may now propose our own views of the order of the parts in generation as we have gathered it from our observations, it appears that the whole business of generation in all animals may be divided into two periods, or connected with two structures: the ovum, i. e. the conception and seed, or that, whatever it be, which in spontaneous productions corresponds to the seed, whether with Fernelius it be called “the native celestial heat in the primogenial moisture,” or with Aristotle, “the vital heat included in moisture.” For the conception in viviparous animals, as we have said,...

      • EXERCISE THE FIFTY-SEVENTH. Of certain paradoxes and problems to be considered in connexion with this subject.
        (pp. 426-434)

        Thus far have we spoken of the order of generation, whereby the differences between those creatures that are engendered by metamorphosis and those that are developed by epigenesis, as well as between those that are said to proceed from a worm and those that arise from an egg, have been made to appear. The latter are partly incorporated from a prepared matter, and are nourished and increased from a certain remaining matter; the former are incorporated from the whole of the matter present; the latter grow and are formed simultaneously, and after their birth continue to wax in size and...

      • EXERCISE THE FIFTY-EIGHTH. Of the nutrition of the chick in ovo.
        (pp. 434-442)

        That the authority of the ancients is not to be rashly thrown off appears in this: it was formerly current doctrine, though many at the present day, Fabricius¹ among the number, reject it as a delusion and a foolish idea, that the embryo sucked in its mother’s womb. This idea nevertheless had Democritus, Epicurus, and Hippocrates for its supporters; and the father of physic contends for it on two principal grounds: “Unless the fœtus sucked,” he says,² “how should excrements be formed? or how should it know how to suck immediately after it is born?”

        Now, whilst in other instances...

      • EXERCISE THE FIFTY-NINTH. Of the uses of the entire egg.
        (pp. 442-444)

        Having now gone through the several changes and processes which must take place in the hen’s egg, in order that it may produce a chick, Fabricius proceeds to consider the uses of the egg at large, and of its various parts; nor does he restrict himself to the hen’s egg, but condescends upon eggs in general. Among other things he inquires: wherefore some eggs are heterogeneous and composed of different elements; and others are homogeneous and similar? such as the eggs of insects, and those creatures that are engendered from the whole egg, viz. by metamorphosis, and are not engendered...

      • EXERCISE THE SIXTIETH. Of the uses of the yelk and albumen.
        (pp. 444-454)

        “An egg,” says Fabricius,² “properly so called, is composed of many parts, because it is the organ of the engenderer, and Galen everywhere insists on the constitution of an organ as implying multiplicity of parts.” But this view leads us to ask whether every egg must not be heterogeneous, seeing that every egg is organic? And every egg, indeed, even that of the fish and insect, appears to be composed of several different parts,—membranes, coverings, defences; nor is the included matter by any means without diversity of constitution in different parts.

        Fabricius agrees farther, and correctly, with Galen, when...

      • EXERCISE THE SIXTY-FIRST. Of the uses of the other parts of the egg.
        (pp. 454-456)

        The shell is hard and thick that it may serve as a defence against external injury to the fluids and the chick it includes. It is brittle, nevertheless, particularly towards the blunt end, and as the time of the chick’s exclusion draws near, doubtless that the birth may suffer no delay. The shell is porous also; for when an egg, particularly a very recent one, is dressed before the fire, it sweats through its pores. Now these pores are useful for ventilation; they permit the heat of the incubating hen to penetrate more readily, and the chick to have supplies...

      • EXERCISE THE SIXTY-SECOND. An egg is the common origin of all animals.
        (pp. 456-461)

        “Animals,” says Aristotle,¹ “have this in common with vegetables, that some of them arise from seed, others arise spontaneously; for as plants either proceed from the seed of other plants, or spring up spontaneously, having met with some primary condition fit for their evolution, some of them deriving their nourishment from the ground, others arising from and living on other plants; so are some animals engendered from cognate forms, and others arise spontaneously, no kind of cognate seed having preceded their birth; and whilst some of them are generated from the earth, or putrefying vegetable matter, like so many insects,...

      • EXERCISE THE SIXTY-THIRD. Of the generation of viviparous animals.
        (pp. 461-466)

        Thus far have we treated mainly of the generation of oviparous animals; we have still to speak particularly of the other species of generation, the viviparous, to wit, in which many things identical with those we have noticed in oviparous generation will come to be observed. These we have reduced into order, and here at length present for consideration. Even the parts that appear paradoxical and in contradiction with the current views of generation will, I believe, be found entirely in conformity with truth.

        Among viviparous animals, man, the most perfect of all creatures, occupies the foremost place; after him...

      • EXERCISE THE SIXTY-FOURTH. The generation of viviparous animals in general is illustrated from the history of that of the hind and doe, and the reason of this selection.
        (pp. 466-467)

        It was customary with his Serene Majesty, King Charles, after he had come to man’s estate, to take the diversion of hunting almost every week, both for the sake of finding relaxation from graver cares, and for his health; the chase was principally the buck and doe, and no prince in the world had greater herds of deer, either wandering in freedom through the wilds and forests, or kept in parks and chases for this purpose. The game during the three summer months was the buck, then fat and in season; and in the atumn and winter, for the same...

      • EXERCISE THE SIXTY-FIFTH. Of the uterus of the hind and doe.
        (pp. 467-474)

        About to treat of the generation of the hind and doe, our first business will be to speak of the place where it proceeds, or of the uterus, as we have done above, in giving the history of the common fowl, by which all that follows will be more easily and readily understood. And history has this great pre-eminence over fable, that it narrates the events which transpired in certain places at certain times, and therefore leads us to knowledge by a safe and assured way.

        Now that we may have a clearer idea of the uterus of the hind,...

      • EXERCISE THE SIXTY-SIXTH. Of the intercourse of the hind and doe.
        (pp. 474-476)

        So much for the account of the uterus of the female deer, where we have spoken briefly upon all that seemed necessary to the history of generation, viz. the ‘place’ of conception, and the parts instituted for its sake. We have still to speak of the action and office of this ‘place,’ in other words, of intercourse and conception.

        The hind and doe admit the male at one and only one particular season of the year, namely, in the middle of September, after the Feast of the Holy Cross; and they bring forth after the middle of June, about the...

      • EXERCISE THE SIXTY-SEVENTH. Of the constitution or change that takes place in the uterus of the deer in the course of the month of September.
        (pp. 476-478)

        We now come to the changes that take place in the genital parts of the female after intercourse, and to the conception itself. In the month of September, then, when the female deer first comes in season, her cornua uteri, uterus, or place of conception, grows somewhat more fleshy and thick, softer also, and more tender. In the interior of either cornu, at that part, namely, which looks drawn together by a band, and is turned towards the spine, we observe, protruding in regular succession, five caruncles, soft warts, or papillæ. The first of these is larger than any of...

      • EXERCISE THE SIXTY-EIGHTH. Of what takes place in the month of October.
        (pp. 478-482)

        Repeated dissections performed in the course of the month of October, both before the rutting season was over and after it had passed, never enabled me to discover any blood or semen, or a trace of anything else, either in the body of the uterus or in its cornua. The uterus was only a little larger, and somewhat thicker; and the caruncles were more tumid and florid, and, when strongly pressed with the finger, discharged small drops of blood, much in the manner in which a little watery milk can be squeezed from the nipples of a woman in the...

      • EXERCISE THE SIXTY-NINTH. Of what takes place in the uterus of the doe during the month of November.
        (pp. 482-492)

        Taught by the experience of many years I can state truly that it is from the 12th to the 14th of November that I first discover anything which belongs to the future offspring in the uterus of the hind.

        I remember, indeed, that in the year of grace 1633, the signs of conception, or the commencements of the embryos, made their appearance somewhat earlier; because the weather was then cloudy and wet. In does, too, which have rutted six or seven days sooner than hinds, I have always discovered something of the future foetus about the 8th or 9th of...

      • EXERCISE THE SEVENTIETH. Of the conception of the deer in the course of the month of December.
        (pp. 492-501)

        In the beginning of December the foetus is seen larger, every way more perfect, and the length of the finger. The heart and other viscera which formerly hung externally are now concealed within the cavities of the body, so that they can no longer be seen without dissection.

        The conception, or ovum, by the medium of the five caruncles which we have already spoken of as present in either cornu, is now in connexion with the uterus at an equal number of points; still the union is not so strong but that a very slight rather than a great effort...

      • EXERCISE THE SEVENTY-FIRST. Of the innate heat.
        (pp. 501-512)

        As frequent mention is made in the preceding pages of thecalidum innatum,or innate heat, I have determined to say a few words here, by way of dessert, both on that subject and on thehumidum primigenium,or radical moisture, to which I am all the more inclined because I observe that many pride them- selves upon the use of these terms without, as I apprehend, rightly understanding their meaning. There is, in fact, no occasion for searching after spirits foreign to, or distinct from, the blood; to evoke heat from another source; to bring gods upon the scene,...

      • EXERCISE THE SEVENTY-SECOND. Of the primigenial moisture.
        (pp. 513-518)

        We have now dignified the blood with the title of the innate heat; with like propriety, we believe, that the fluid which we have called the crystalline colliquament, from which the foetus and its parts primarily and immediately arise, may be designated the radical and primigenial moisture. There is certainly nothing in the generation of animals to which this title can with better right be given.

        We call this the radical moisture, because from it arises the first particle of the embryo, the blood, to wit; and all the other posthumous parts arise from it as from a root; and...

      (pp. 521-548)

      On generation follows parturition, that process, viz. by which the foetus comes into the world and breathes the external air. I have, therefore, thought it well worth while, and within the scope of my design, to treat briefly of this subject. With Fabricius, then, I shall consider the causes, the manner, and the seasons of this process, as well as the circumstances which both precede and follow it. The circumstances which occur immediately previous to birth, and which, in women especially, indicate that the act of parturition is not far distant, are, on the one hand, such a preparation and...

      (pp. 551-572)

      “Four kinds of bodies” are enumerated by Hieronymus Fabricius¹ “as existing externally to the foetus; these are the umbilical vessels, the membranes, the humours, and a fleshy substance.” On these subjects, guided by my observations, I shall briefly state wherein I differ from him; first, however, giving his statement in his own words.

      “There are,” he says, “three membranes, two of which envelope the whole foetus, but the third does not do so. Of those which envelope the whole foetus, the innermost, immediately investing one, is called άμυιου, i. e. the mantle. That which follows next is entitled by the...

      (pp. 573-586)

      Fabricius has indeed recounted many wonderful things on the subject of parturition; for ray own part, I think there is more to admire and marvel at in conception. It is a matter, in truth, full of obscurity; yet will I venture to put forth a few things—rather though as questions proposed for solution—that I may not appear to subvert other men’s opinions only, without bringing forward anything of my own. Yet what I shall state I wish not to be taken as if I thought it a voice from an oracle, or desired to gain the assent of...

      (pp. 589-592)

      Thomas Pare, a poor countryman, born near Winnington, in the county of Salop, died on the 14th of November, in the year of grace 1635, after having lived one hundred and fifty-two years and nine months, and survived nine princes. This poor man, having been visited by the illustrious Earl of Arundel when he chanced to have business in these parts, (his lordship being moved to the visit by the fame of a thing so incredible,) was brought by him from the country to London; and, having been most kindly treated by the earl both on the journey and during...

    • LETTER I. To Caspar Hofmann, M.D. Published at Nurenberg, in the ‘Spicilegium Illustrium Epistolarum ad Casp. Hofmannum.’
      (pp. 595-596)

      Your opinion of me, my most learned Hofmann, so candidly given, and of the motion and circulation of the blood, is extremely gratifying to me; and I rejoice that I have been permitted to see and to converse with a man so learned as yourself, whose friendship I as readily embrace as I cordially return it. But I find that you have been pleased first elaborately to inculpate me, and then to make me pay the penalty, as having seemed to you “to have impeached and condemned Nature of folly and error; and to have imputed to her the character...

    • LETTER II. To Paul Marquard Slegel, of Hamburg.
      (pp. 596-603)

      I congratulate you much, most learned sir, on your excellent commentary, in which you have replied in a very admirable manner to Riolanus, the distinguished anatomist, and, as you say, formerly your teacher: invincible truth has, indeed, taught the scholar to vanquish the master. I was myself preparing a sponge for his most recent arguments; but intent upon my work ‘On the Generation of Animals’ (which, but just come forth, I send to you), I have not had leisure to produce it. And now I rather rejoice in the silence, as from your supplement I perceive that it has led...

    • LETTER III. To the very excellent John Nardi, of Florence.
      (pp. 603-603)

      I should have sent letters to you sooner, but our public troubles in part, and in part the labour of putting to press my work ‘On the Generation of Animals,’ have hindered me from writing. And indeed I, who receive your works—on the signal success of which I congratulate you from my heart—and along with them most kind letters, do but very little to one so distinguished as yourself in replying by a very short epistle. I only write at this time that I may tell you how constantly I think of you, and how truly I store...

    • LETTER IV. In reply to R. Morison, M.D., of Paris.
      (pp. 604-610)

      Illustrious Sir,—The reason why your most kind letter has remained up to this time unanswered is simply this, that the book of M. Pecquet, upon which you ask my opinion, did not come into my hands until towards the end of the past month. It stuck by the way, I imagine, with some one, who, either through negligence, or desiring himself to see what was newest, has for so long a time hindered me of the pleasure I have had in the perusal. That you may, therefore, at once and clearly know my opinion of this work, I say...

    • LETTER V. To the most excellent and learned John Nardi, of Florence.
      (pp. 610-611)

      Distinguished And Accomplished Sir,—The arrival of your letter lately gave me the liveliest pleasure, and the receipt at the same time of your learned comments upon Lucretius satisfied me that you are not only living and well, but that you are at work among the sacred things of Apollo. I do indeed rejoice to see truly learned men everywhere illustrating the republic of letters, even in the present age, in which the crowd of foolish scribblers is scarcely less than the swarms of flies in the height of summer, and threatens with their crude and flimsy productions to stifle...

    • LETTER VI. To John Daniel Horst, principal Physician of Hesse-Darmstadt.
      (pp. 612-613)

      Excellent Sir,—T am much pleased to find, that in spite of the long time that has passed, and the distance that separates us, yon have not yet lost me from your memory, and I could wish that it lay in my power to answer all your inquiries. But, indeed, my age does not permit me to have this pleasure, for I am not only far stricken in years, but am afflicted with more and more indifferent health. With regard to the opinions of Riolanus, and his decision as to the circulation of the blood, it is very obvious that...

    • LETTER VII. To the distinguished and learned John Dan. Horst, principal Physician at the Court of Hesse-Darmstadt.
      (pp. 613-615)

      Most excellent Sir,—Advanced age, which unfits us for the investigation of novel subtleties, and the mind which inclines to repose after the fatigues of lengthened labours, prevent me from mixing myself up with the investigation of these new and difficult questions: so far am I from courting the office of umpire in this dispute! I was anxious to do you a pleasure lately, when, in reply to your request, I sent you the substance of what I had formerly written to a Parisian physician as my ideas on the lacteal veins and thoracic ducts.¹ Not, indeed, that I was...

    • LETTER VIII. To the very learned John Nardi, of Florence, a man distinguished alike for his virtues, life, and erudition.
      (pp. 615-616)

      Most excellent Sir,—I lately received your most agreeable letter, from which I am equally delighted to learn that you are well, that you go on prosperously, and labour strenuously in our chosen studies. But I am not in formed books forwarded at the same time, have come to hand or not. I should be happy to have news on this head at your earliest convenience, and also to be made acquainted with the progress you make in your ‘Noctes Geniales,’ and other contemplated works. For I am used to solace my declining years, and to refresh my understanding, jaded...

    • LETTER IX. To the distinguished and accomplished John Vlackveld, Physician at Harlem.
      (pp. 616-618)

      Learned Sir,—Your much esteemed letter reached me safely, in which you not only exhibit your kind consideration of me, but display a singular zeal in the cultivation of our art.

      It is even so. Nature is nowhere accustomed more openly to display her secret mysteries than in cases where she shows traces of her workings apart from the beaten path; nor is there any better way to advance the proper practice of medicine than to give our minds to the discovery of the usual law of nature, by the careful investigation of cases of rarer forms of disease. For...

    (pp. 619-624)