The anatomical exercises of Dr. William Harvey professor of physick, and physician to the Kings Majesty, concerning the motion of the heart and blood. [Part 3] Two anatomical exercitations concerning the circulation of the blood to John Riolan the son ... With the preface of Zachariah Wood physician of Roterdam. To which is added Dr. James De Back his Discourse of the heart, physician in ordinary to the town of Roterdam.
Harvey, William, 1578-1657.

The First ANATOMICAL EXERCITATION Concerning The Circulation of the Blood, To JOHN RIOLAN.

THere did come forth not many moneths agoe a little piece of the most famous Riolan's, concer∣ning Anatomie and Dis∣eases; for which, as being sent to me by the Author himself, I return hearty thanks: Seriously I do con∣gratulate the felicity of that man in under∣taking a thing very commendable. To open to the view the seats of all Diseases, is a work not to be atchiev'd but by a di∣vine wit; Truly he undertook a hard task, that has set those Diseases, which are al∣most obscure to our understanding, before our eyes. Such endeavours become the Prince of Anatomists; for there is no Sci∣ence Page  2which has not its beginning from foregoing knowledge, nor any knowledge which is not beholding to sense for its ori∣ginal: For which cause the business it self, and the example of so worthy a person re∣quir'd my pains, and did invite me in like manner to put forth and joyn my medici∣nal Anatomic, being chiefly fitted for Phy∣sical uses, not with the same intention as he, by demonstrating the places of disea∣ses, from the dead bodies of healthful men, and rehearsing the divers sorts of diseases incident to those places, according to o∣ther mens opinions, which he ought to have seen there; but that I might under∣take to relate from the many dissections of sick bodies, and the most grievous and wonderfull diseases of dead persons, in what manner, and how the inward parts of them are chang'd, in place, bignesse, condition, figure, substance, and other sensible accidents, from their natural form and appearance, which all Anatomists commonly describ'd, and how diversly and wonderfully they are affected. For as the dissection of healthfull and well habited bodies conduces much to Philosophie and right Physiologie, so the inspection of di∣seased bodies conduces chiefly to Patho∣logical Philosophie. For the Physiological contemplation of those things which are according to Nature, is first to be known Page  3by the Physician, for that which is accor∣ding to Nature is right, and is rule both to it self and that which is amisse; by the light of which, errors and preternatural diseases being defin'd, Pathologie is more clear, and from Pathologie the use and art of administring Physick, and occasions of inventing many new remedies doe ocur. Nor will any man beleeve how much in diseases, especially such as are Chronical, the inwards are chang'd, and what mon∣strous shapes of the inward parts are be∣gotten by diseases: And I dare say the opening and dissection of one consump∣tive person, or of a body spent with some antient or venemous disease, has more en∣rich'd the knowledge of Physick, than the dissections of ten bodies of men that have been hang'd.

Yet doe not I disallow of the most fa∣mous and most learned Anatomist Riolan his purpose, but think it highly to be com∣mended, as being very profitable for Phy∣sick, that he does illustrate the Physiolo∣gical part; yet did I think that it would not be lesse profitable to the art of Phy∣sick if I should set clearly before your eys to be seen, not only the places, but like∣wise the diseases of those places, and re∣hearse them, after I had well view'd and observ'd them, and from my many dis∣sections declare my experience.

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But such things in that Book con∣cerning the Circulation of the blood found out by me, which are translated, and seem to reflect onely upon me, must first and chiefly be taken into consideration by me. For so great a mans judgement, concer∣ning such a weighty businesse, is not to be set at nought (who is undoubtedly thought the chief, and ringleader of all A∣natomists of this age) but the opinion of him alone, is more to be weigh'd for com∣mendation, than the verdicts of all others, which shall either applaud or contradict me, and his censure more to be weigh'd and look'd upon. He then in his lib. 3. cap. 8. Enchir. acknowledges our motion of the blood in Animals, and takes part with us, and is of our opinion, as concer∣ning the circulation of the blood: yet not altogether, and openly; for he says, lib. 2. cap. 21. That the blood in the port vein contained, admits no circulation, as the blood in the vena cava, and in lib. 3. cap. 8. That there is blood which is circulated, and circulatory vessels, to wit, the aorta and the vena cava, yet he denies that the branches of them have a∣ny circulation; Because, says he, the blood running out into all the parts of the second and third region, stayes there for nutrition, nor does it flow back to the grea∣ter vessels, but being pluck'd back by force, Page  5when the greater vessels are in great want of blood, or when it returns with a sudden force, or exstimulation, to the greater circu∣latory vessels. And so a little after. Whe∣ther or no the blood of the veins, does per∣petually or naturally ascend, or whether it returns to the Heart, or Whether the blood of the Arteries do descend, or go from the Heart, yet if the lesser veins of the arms and leggs be empty, the blood of the veins in succession filling the empty places, may des∣cend, which (sayes he) I have clearly de∣monstrated against Harvey and Wallaeus. And because daily experience and the au∣thority of Galen does comfirm the Anasto∣mosis of the veins & arteries, & the necessi∣ty of the Circulation of the blood; You see, sayes he, how the circulation of the blood coms about, without the confusion of humors, or the perturbation of antient medicine.

By which words it is known, for what cause the most famous man would partly acknowledge, partly deny the Circulation of the blood, and why he endeavours to build a reeling and tottering opinion of Circulation. Lest, forsooth, he should de∣stroy the antient Physick, and not mov'd by truth, which he could not chuse but see, but rather for fear he should violate the antient rules of Physick, or perchance, lest he ssould seem to resume or retract that Physiologie which in his Anthropolo∣giaPage  6he had publish'd before. For the Cir∣culation of the Blood does not destroy the antient Physick, but furthers it; rather it show the Physiologie of Physicians, and the speculation of natural things, and disallows the Anatomical doctrine of the use and action of the heart, lungs; and the rest of the intrals; and that these things are so, will appear partly out of his own words, partly out of those things which I shall here set down; namely, that the whole blood, in whatsoever part of the body living it be, does move and shift place (as well that which is in the greater veins, and their branches and fibers, as that in the porosities of the parts in any region of the body) does flow to the heart, & flow from the heart, without interruption, incessantly, and never continues in one place without damage; though I do not say, but in some places it moves flower, in some faster.

First then, the most learned man de∣nyes only that the blood contain'd in the Porta does circulate, which he could nei∣ther have denied nor disapproved of, if he had not pass'd over the force of his own argument: for he sayes lib. 3. cap. 8. If in every pulsation the heart receive one drop of blood, which it expels into the aorta, and does make two thousand pulsations in an hour, there must needs a great deal of blood Page  7passe through. He is likewise forc'd to affirm the same of the mesenterie, since through the caliacal arterie, and the me∣senterial arteries, there is thrust in more than one drop of blood at every pulsati∣on, and is forc'd against the mesenterie and its veins: insomuch that it must either go out according to the just proportion of that which enters, otherwise the branches of the Porta would burst at last; nor can it (for the resolution of this doubt) be pro∣bably said, or possibly be, that the blood of the mesenteric should vainly, and to no purpose, ebb and flow through these arte∣ries, like an Euripus; nor the relapse from the mesenteric by those passages and transplantation by which he would have the mesenteric disgorge it self into the aorta, likely to be true; nor can it prevail against that which is entring by contrary motion; nor can there be any vi∣cissitude, where it is most certain that without interruption, and incessantly, there is an influx; but is compell'd by the same necessity, by which it is certain, that the heart doth thrust forth the blood a∣gainst the mensenteriū. Which is most ma∣nifest; for otherwise, by the same argu∣ment, they would overthrow all Circula∣tion of the blood, if thus he should, with the same likelihood of truth, affirm that too in the ventricles of the heart, namely Page  8in the Systole of the heart the blood is driven into the aorta, and in the Diastole returns, and the aorta disburthens it self into the ventricles of the heart, as the ventricles again into the aorta, and so neither in the heart nor in the mesenterie should there be any circulation, but a flux and reflux, by turns, is turned up and down with needlesse labour: Therefore if of necessity in the heart is proved the circulation of the blood, for the reason a∣foresaid prov'd by himself, the same force of argument takes place likewise in the mesenterie; but if there be no circulation in the mesenterie, neither is there in the heart; for both these assertions, namely, this of the heart, that of the mesenterie, hangs upon the force of the same argu∣ment, onely changing the words, and is establish'd, and falls in like manner.

He sayes, that the Sigma-like portals do hinder the regresse of the blood in the heart, but there are no portals in the me∣senterie.

I answer, neither is this true; for in the splenick branch, as likewise sometimes in others, there are found portals. Besides, portals are not all times requisite in the more profound veins, nor are they found in the deep veins of the joints, but rather in the skin veins; for where the blood flowing out of the lesse branches is prone Page  9naturally to come into the greater, by the compression of the muscles about it it is sufficiently hinder'd from return, but where the passage being open, it is forc'd; What need is there there of por∣tals? But how much blood at every pulsation is forc'd into the mesente∣rie, is reckoned according to the same ac∣count, as if with an indifferent ligature you should in the carpus bind the veins comming out of the hand, and entring in∣to the arteries; (for the arteries of the me∣senterie are greater than those of the car∣pus) if you tell at how many pulsations the vessel and your whole hand swell to their greatest biguesse dividing and ma∣king a subduction, you shall find much more than one drop of blood come in at every pulsation, notwithstanding the ligature; nor can it return, but rather that in filling the hand it forcibly distends and swels it, we may by calculation gather, that the blood enters the mesenteric in the same quantity, if not in a greater, by how much the arteries of the mesenteric are greater than those of the carpus. And if any should but see and think with himself, with what difficultie and pains, compres∣sions, ligatures, and severall means the blood is staid, that leaps forcibly out of the least arterie which is cut or broken, with what strength (as if it were shot out of a Page  10spout) it throws off, and drives away, or passes through all the bindings, I think he would scarce beleeve that any part of blood which only enters, could against this impulsion and influx passe back again, being not able to drive it back with force. For which cause, considering these things with himself, I beleeve it would not ever enter his mind to imagin that the blood out of the veins of the porta could creep back by these same wayes, and so disbur∣then it self into the Mesenterie, against so forcible and strong an influx into the ar∣teries.

Moreover, if the most learned man be∣leeve not that the blood is mov'd and chang'd by circular motion, but being still the same, it stands and mantles in the branches of the mesenterie; he seems to suppose, that there is a two-fold blood, divers, and serving to divers uses and ends, and therefore it is of divers natures in the vena porta and cava, because one of them for its preservation needs circulation, the other needs not, which neither does it ap∣pear, nor does he demonstrate it to be true.

Besides the most learned man addes in his Enchirid. lib. 2. cap. 18. A fourth sort of vessels to the Mesenterie, which are cal∣led the Venae Lacteae (invented by Asselius) which being set down, he seems to infer that Page  11all the nutriment being drawn through them is carried to the liver, the forge of blood, which being there concocted and changed into blood, (he says in lib. 3. cap. 8.) it is carried to the left ventricle of the heart, which being granted, sayes he, all the scru∣ples which were antiently motion'd concer∣ning the distribution of the Chylus, and of the blood through the same conduit, do cease, for the Venae Lacteae carry the Chylus to the Liver, and therefore these conduits are a∣part, and can be obstructed apart. But in∣deed I would fain know how this can be demonstrated to be true; If this milk be transfus'd and passe into the liver, how shall it get thence through the cava into the ventricle of the heart? (Since the most learned man denyes that the blood con∣tained in the numerous branches of the porta and the liver can passe, that so circu∣lation may be made) but more especially since the blood seems to be a great deal fuller of spirit, and more penetrative than the milk or chylus, which is contain'd in these vessels, and is hitherto impell'd by the arteries that it may find out some way for its self.

The most learned man makes mention of a certain Treatise of his concerning the Circulation of the blood, I wish I could see it, I might perchance recant.

But if the most learned man thought it Page  13more fit to place the circular motion of the blood in the veins of the porta, and branches of the cava, (as he says in his 3. Book Chap. 8. In the veins the blood does perpetnally and naturally ascend or return to the heart, as likewise that which is in all the arteries descends and departs from the heart. I say, I do not see, but upon this po∣sition all difficulties which were objected of old of the distribution of the Chylus, & blood, through these same conduits, should likewise cease, that hence forward he should not need to enquire apart for, or to set down vessels for the chylus; seeing as the Umbilical veins do draw their nu∣tritive juice from the liquors of the egg, and carries it to the nourishing and aug∣mentation of the Chick whilst it is yet an Embryon, so do the meseraick veins suck the chylus from the intestines, and carry it to the liver, and what hinders us to assert, that it does the like in those of riper age? for all difficulties cease, when there are not two contrary motions supposed in the same vessels; but that we do suppose that there is one continued motion in the me∣seraicks from the intestines to the Liver.

I shall tell you in another place what is to be thought of the venae Lacteae, when I shall speak of milk found in several parts of creatures new born, especially in man∣kind, for it is found in the mesenterie and Page  12all its glandules, as also in the chymus, likewise in the arm-pits and paps of Chil∣dren; the Midwives milk out the blood for their health as they beleeve.

But moreover it pleas'd the most lear∣ned Riolan, not only to deprive the blood contain'd in the mesenterie of circulation, but also he affirms, that neither the bran∣ches of the vena cava, or its arterie, or any part of the second or third region ad∣mits of circulation, so that only he cals the vena cava & the aorta circulatory vessels, for which in his 3 Book Chap. 8. he gives a very faint reason, Because the blood, sayes he, flowing into all parts of the second and third region remains there for nou∣rishment nor does it flow back to the grea∣ter vessels, unless it be revulsed by the force and want of blood in the greater vessels, or flow back, being stirr'd with a sudden force, to the circulatory vessels.

It is indeed of necessity, that the portiō which passes into nourishment, should re∣main, for otherwise it should not nourish unless it be assimilated, & stay there, in lieu of that which is lost, & so become one: but it is not needfull, that the whole influx of blood should remain there for the conver∣sion of so little a portion; for every part does not use so much blood for its nou∣rishment, as it contains in its veins, arte∣ries, and porosities, nor is it necessary Page  14in his afflux and reflux that it should leave no nourishment within it; where fore it is not necessary that for nutrition it should all stay, but likewise the most learned man himself, in the very same book in which he affirms this, does seem every where almost to affirm the contrary, es∣pecially where he sets down the circulati∣on in the brain, and by circulation (sayes he) the brain does send back blood to the heart, and so the heart is refrigerated. After which sort likewise, the remote parts may be said to refrigerat the heart, whence also in feavers, when the parts about the heart are grievously scorched and inflam'd with feaverish heat, laying naked their joints, and throwing off the cloaths, sick people endeavor to cool their heart, whilst (as the most learned man affirms of the brain) the blood being refrigerated and allayd of its heat, do's then go to the heart through the veins, and does refrigerat it. Whence the most learned man seems to insinuate a kind of necessity, that as from the brains, so there is a circulation from all the parts, otherwise than before he had openly declar'd. But indeed he cautiously and ambiguously affirms. That the blood does not flow back from the parts of the second and third region, unlesse, says he being revuls'd by the force and great want of blood in the bigger vessels, or that it Page  15does by a sudden forcible motion flow back to the greater circulatory vessels, which is most true, if these words be un∣derstood in a true sense; for by the grea∣ter vessels, in which he says want causes a reflux. I beleeve he understands the vena cava, or the circulatory veins, not the ar∣teries; for the arteries are never empty∣ed, but into the veins, or pores of the parts, but they are continually stuff'd full by the pulse of the heart. If all the parts did not incessantly refund blood in abundance in∣to the vena cava, and the circulatory ves∣sels, out of which the blood very sudden∣ly passes, and hastens to the heart, there would quickly be a great want of blood. Besides that, the blood which is contai∣ned in all the parts of the second and third region, by the force of the blood direct∣ed and driven by every pulse, is fore'd out of the pores into the veins, out of the branches into the greater vessels, as like∣wise by the motion and compression of the parts adjacent; for that which is con∣tain'd is thrust out by every thing contai∣ning it, when it is press'd and streight∣ned: so by the motion of the muscles and the joints, the branches of the veins pas∣sing between being press'd and streight∣ned, thrust the blood contain'd in the les∣ser vessels into the greater.

But it is not to be doubted, that the Page  16blood is continually and incessantly dri∣ven, and comes with force from the arte∣ries, and never flows back; if it be admit∣ted, that in every pulse all the arteries to∣gether are distended by the propulsion of blood, and that the Diastole of the arte∣ries, as the most learned man confesses, is from the Systole of the heart; nor does the blood once gone forth, return into the ventricles of the heart, by reason that the portals are shut, if (I say) the most lear∣ned man do beleeve these things, as it seems he does, it will easily be understood in every part of what region soever, by what stuffing or impulsion the blood in them contained is forcibly thrust down.

For so far as the arteries beat, so far reaches the influx and the force, where∣fore it is felt in all parts of every region, for there is a pulse every where in the tops of our fingers, and under the nails, nor is there any part in our whole body, either sore with boil or fellon, which does not feel the pricking motion of the beating of the arterie, and its endeavour to dis∣solve the continuum.

But further it is manifest, that the blood does make a regresse in the pores of the parts, in the skin of the hands and feet, for sometimes in great frost and cold seasons we see the hands and joints, especially of boys, so cold, that at the very touch they Page  17do almost resemble the coldnesse of Ice, and are so benummed and stiff, that there is scarce any life in them, nor motion, and yet in the mean time they are full of blood seeming red or blew, which parts can again by no means be warm'd, unlesse by Circulation that refrigerate blood be thrust out, and in its place, new, warm, and spirituous blood flowing in do foment and re-warm the parts, and restore to them motion and sense; for they should never be renew'd or restor'd by external heat, no more than the members of dead per∣sons, unless some internal influent warmth did refresh them. This indeed is the chief use & end of the Circulation of the blood, for which cause, the blood by its continual course, and perpetual influence, is driven a∣bout; namely, that all the parts depending upon it by their first innate warm moisture might be retain'd in life, and in their own vital and vegetative essence, and perform all their functions, whilst (as the Natural∣lists say) they are sustain'd and actuated by natural heat, and vital spirits; so by the help of two extremities, heat and cold, the temper of the bodies of creatures is kept in its mediocrity: for as the breathing in of air does temper the too much heat of the blood in the lungs, and in the centre of the body, and causes the eventilation of suffocating fumes; so also the blood being Page  18hot, and cast out through the arteries into the whole body, does foment and nourish the extremities in living creatures and hin∣ders them to be extinguish'd by the force of outward cold.

Therefore it were injust and wonder∣full, if every little part of what region so∣ever should not enjoy the benefit of the transmutation and circulation of the blood, for whose sake Circulation seems chiefly to be appointed by Nature. There∣fore, that I may conclude, for you see how the Circulation of the blood is per∣form'd without perturbation or confusion of the humors, in all the body, and in eve∣ry part, both in the greater and in the les∣ser vessels, and that by necessity, and for the benefit of all the parts, without which, being cold and impotent, they could never be restor'd, or remain alive. It is enough, because its clear, that all influence of pre∣servative heat does come through the ar∣teries, and is done by circulation.

For which cause most learned Riolan seems to me, when he sayes, that in some parts there is no Circulation, to speak rather officiously, than truth; to wit, that he might please most men, and oppose no body, and that he rather wrote humane∣ly, than gravely, in the behalf of the truth. As he likewise seems to do (lib. 3. cap 8.) when he would rather have the blood to Page  19come into the left ventricle through the septum of the heart, through uncertain and hidden passages, than through the large and most open vessels of the lungs, be∣ing made with Portals artificially to hin∣der its return. I desire to see the reason of the impossibility and inconvenience which he says he propounded elsewhere. It is a wonder, since the Aorta and ve∣na Arteriosa, are of the same bignesse, constitution, and frame, that their fun∣ction should not be the same. But that is very improbable that the great River of the whole masse of blood should in so great abundance go into the left ventri∣cle by so blind and small a winding of the septum, which should answer both to the entrie from the vena cava in the right side of the heart, and also its egresse from the left, which do both require such wide orifices. But he has likewise produc'd these things staggeringly, for in lib. 3. ca 6. he ordains the lungs as a sink or passage from the heart, and he says, The lungs are affected by that blood which passes through, whilst its filth flowes together with that blood; so he sayes likewise, That the lungs acquire corruption by distemper'd, and ill-conditi∣on'dintralls, which furnish the heart with impure blood, whose fault the heart cannot help, but by many circulations. He like∣wise Page  20in the same place, concerning letting of blood, and shortnesse of breath, & com∣munication of the veins with the vessels of the lungs, says against Galen, If it be rue that the blood does naturally passe from the right ventricle of the heart to the lungs that it may be carryed to the left ventricle, and so to the aorta; and if the Circulation of the blood be admitted, who sees not in the dis∣eases of the lungs, that the blood flows thi∣ther in greater abundance, and oppresses the lungs, unlesse they be first largely emptied, every part taking a share to case them; which was Hippocrates advice, from all parts of the body, head, nose, tongue, arms, feet, to take away the blood, that the quantity of it might be impaired, and that it might be re∣vulsed from the lungs, and so draws out the blood till the body was quite without blood. He says likewise, The Circulation being suppos'd, the lungs are easily emptied by breathing a vein. If this counsel be rejected, I see not how it can be revuls'd from thence; for if it flow back through the vena arteriosa into the right ventricle, the Sigmoidal por∣tals hinder it, and the three-pointed portals hinder the regress out of the right ventricle into the vena cava. Therfore by Circulation the bload will be exhausted, by cutting the veins of the arms and feet. And likewise Pernelius his opinion in the affections of the lungs is destroy'd, that blood is rather to be Page  21taken out of the right arm than out of the left, for the blood cannot return into the ve∣na cava, unlesse it break through two gates and bars which are placed in the heart.

He addes moreover in the same place, (lib. 3. cap. 6.) If the Circulation of the blood be admitted, and that it doth pass of∣ten through the lungs, and not through the middle of the Septum of the heart, there is a two-fold Circulation of the blood to be as∣signed, one of which is perfected by the heart and the lungs, whilst the blood leaping out from the right ventricle of the heart is car∣ried through the lungs, that it may come to the left ventricle of the heart; for leaping out from the same inward part, it returns to it, then by another larger circulation flowing out of the left ventricle of the beart, it goes about the whole body, and runs through the arteries and veins to the right ventricle of the heart.

The most learned man in this place might have added the third circulation, which is a very short one, out of the left ventricle into the right, drawing about a part of the blood through the coronall arteriese and veins, by its branches, which are distributed about the bodie, walls, and septum of the heart.

He says, He that admits of one circula∣tion, cannot deny the other. So might he have added, nor can he refurse the third. Page  22For to what purpose should the coronal arteries beat in the heart, if they did not drive blood thither? and why should the veins, (whose function and end it is to re∣ceive blood put into them by the arteries) but that they might draw blood from the heart? Moreover in the orfice of the Co∣ronal arterie (as the learned man himself confesses, in his third Book and his ninth Chapter,) there is a portal which forbids, all entrance, and is patent to egresse: therefore truely he cannot but admit of the third Circulation, who likewise admits of another universal one, and that the blood does likewise passe through the lungs and the brain, (lib. 4. cap. 2.) For neither can there be an admittance of blood by pulsation, in all parts of every region, nor regresse by the veins after the same manner, and therefore he cannot de∣ny, but that the parts admit of Circula∣tion.

Therefore it is clear from these very words of the most learned man, what his opinion is, both of the Circulation of the blood through the whole bodie, as like∣wise through the lungs and the rest of the parts; for the that admits of the first Cir∣culation, it is clear that he does not reject the other: For how can it be, that he who has admitted of another Circula∣on through the whole body so often, and Page  23through the greater circulatory vessels, should deny that universal Circulation in any of the branches or parts of the second or third region? As if all the veins & those greater circulatory vessels, as he cals them, were not number'd by himself, and by all others, amongst the vessels of the second region. Is it possible that there should be circulation through the whole body, and not through all the parts? and therefore where he denies it he does it very stamme∣ringly, and only staggers and palliates in his negations; there where he affirms he speaks understandingly and as becomes a Philosopher, and as a skilful Physician and an honest man, gives his advice in this case, that in the dangerous diseases of the lungs the letting of blood is the only re∣medy, against Gales and his beloved Fer∣nelius: in which thing if he had been doubtfull, far be it from a Christian and so learned a man, to recommend his expe∣ments to posterity, to procure death, and the hazzard of mens lives, or that he should recede from Fernelius or Galen, men in high esteem with him. Therefore whatsoever he has denyed of the Circula∣tion in the mesenterie, or any other part, in favour of the antient Doctrine of Phy∣sick, or the Venae Lacteae, or for any other regard, it is to be attributed to his civility and modesty, and to be prdoned.

Page  24

I think it does already appear clearly enough, both from the words and the ar∣guments of the most learned man himself, that there is a circulation every where, and that blood wheresoever it is, does change place, and passe through the veins to the heart; and the most learned man seems to be of the same opinion with me; Therefore it needs not, yea it were super∣fluous to bring hither my arguments which I have published in my Book con∣cerning the motion of the blood, for the further confirmation of this truth, which are taken both from the frame of the ves∣sels, placing of the portals, and other ex∣periments and observations; especially since I have not as yet seen the most lear∣nedd mans Treatise of the Circulation of the blood, nor as yet any of the most lear∣ned mans Arguments, but only a bare ne∣gation, by which being induced he should reject the circulation in the regions and vessels, which he allows to be universal in most of the parts.

It is indeed true, that I did find out of the authority of Galen, and by dayly ex∣perience to be a refugium the Anastomosis of the veslels, yet so great a man as he is, so diligent, so curious, so expert an Ana∣tomist, should first have laid open and shown Anastomoses, and those visible and open ones, and whirlpools proportionable Page  25to the imperuous stream of the whole blood, and the orifices of the branches, (from which he has taken away circulati∣on) before he had rejected those which were most probable and most open. He was oblig'd to demonstrate and declare where they are, how they are fram'd, whether they are not onely fit for the in∣tromission of blood (as we see the arte∣ries inserted in the bladder) and not for the return of it, or what other way soever they had been. But perchance I speak too boldly for neither the learned man, nor Galen himself, could by any experience ever behold the sensible Anastomoses, or ever could demonstrate them to the sense.

I did look after them with all possible diligence, and was not at a little charge and pains in the search of the Anastomo∣ses, yet could I never find that any vessell, namely the arteries, together with the veins, were joyn'd by their orifices: I should willingly learn from others who ascribe so much to Galen, that they dare swear all which he says. Nor is there any Anastomosis in the liver, milt, lungs, reins, or any other of the intrals, although I did boyl them till the whole Parenchyme was made mouldering, and like dust was shaken off, and taken away with the point of a needle, from all the fibers of the ves∣sels, Page  26so that I could see the fibers, and the last grains of every division. I dare there∣fore boldy affirm, that neither the vena porta has any Anastomoses with the cava, nor the veins with the arteries, or the ca∣pillar branches of the pore of the choller∣bagg, which are dispers'd about all the flat of the liver with the veins. Only this you may observe in a fresh liver, that all the branches of the vena cava which creep through the whole bunch of the liver, have tunicles pierc'd with many holes like a sive, as it is in a sink, fram'd so for the receiving of the blood which falls down. The branches of the Porta are not so, but are divided into stems, and how that both the divisions of these vessels, the one in the flat, the other in the gibbous part, doe run round to the very furthest rising of that intrall without any Anasto∣moses.

Only in three places doe I find that which is equivalent to an Anastomosis. There rises in the brain, from the soporall arteries creeping down into the Basis, ma∣ny and unintangled fibers, which after∣wards make up the plexus chorois, and pas∣sing through the ventricles doe at last end in the third receptacle, which performs the office of a vein. In the spermaticall vessels, commonly call'd preparatory, lit∣tle arteries drawn from the great arteriePage  27do adhere to the veins preparatory afore∣said, which they accompany, and at last are so receiv'd within their Tuni∣cle, so that at the first they seem both to have one and the same, so that when they end at the upper part of the testicles where that part passes forth into a point, which is called the varicous and vine-like body, we know not what to call them, veins or arteries, or the ends of both. As likewise the last appearances of the arteries which goe to the Vmbilical vein, are obli∣terated in the Tunicles of that vein.

What doubt is to be made, if through such gulphes, the little branches of the arteria magna, swoln with the impul∣sion and instuffing of blood, could be eas'd of so great and so conspicuous a stream? Nature at least would ne∣ver have denyed us visible and sen∣sible passages, sincks and whirlpools, if she had had intention to have tur∣ned all the flux of the blood thither, and by that meanes have deprived the lesser branches, and the solide parts of the benefit of the influx of blood.

Lastly, I will set down one expe∣riment, which seems to be sufficient for the clearing of the Anastomoses, and for the overthrowing of their use, Page  28and of the passage of the blood, and re∣turn of it out of the veins into the ar∣teries, by those wayes.

Opening the breast of any creature, and tying the vena cava by the heart, so that nothing can passe that way in∣to the heart, and presently cutting the jugular arteries, not touching the veins on neither side, If by giving vent you see the arteries emptied, and not the veins too, I hope it will be clear that the blood is carryed out of the veins into the arteries, no where but through the ventricles of the heart. Other∣wise (as Galen has observ'd) in a little space we should see the veins emptyed, and destitute of blood by the efflux of the arteries.

In what remains, Riolan, I both con∣gratulate my self and you, my self for your opinion, with which you have a∣dorn'd my Circulation, as likewise I return to you exceeding thanks for your learned, neat, succinct piece which you sent to me, than which there is nothing more elegant, and I both owe and desire to return deserv'd commendation, but I confess I am not able for such a charge. For I know the name of Riolan will afford more praise to me in its subscription, than my prayses, which I wish as great as may be can do to his Enchiridion. The famous Page  29book shall outlive all memory, and shall recommend your worth to Posterity when all Monuments shall perish. To it you have very handsomly adjoyn'd the Anatomy of Diseases, and have very pro∣fitably enrich'd it with a new Treatise concerning the Bones. May you, most worthy Man, continually increase in this your worth, and love me, who wish that you may be both happy and long liv'd, and that your most famous writings may be an eternall Commendation to you.

William Harvey.