a Skinny Substance or hinder the swallowing of our Meat therefore these annulary Gristles are not made round or entire Circles but where the Gullet touches the Windpipe there to fill up the Circle is only a soft Membrane which may easily give way to the Dilatation of the Gullet And to demonstrate that this was designedly done for this End and Use so soon as the Windpipe enters the Lungs its Cartilages are no longer deficient but perfect Circles or Rings because there was no necessity they should be so but it was more convenient they should be entire Lâ—â—â—ly for the various modulation of the Voice the upper end of the Wind-pipe is endued with several Cartilages and Muscles to contract or dilate it as we would have our Voice Flat or Sharp and moreover the whole is continually moistened with a glutinous Humor issuing out of the small Glandules that are upon its inner Coat to fence it against the sharp Air received in or Breath forced out yet is it of quick and tender Sense that it may be easily provoked to cast out by coughing whatever may fall into it from without or be discharged into it from within Seventhly The Heart which hath been always esteemed and really is one of the principal Parts of the Body the primum vivens ultimum moriens by its uncessant Motion distributing the Blood the Vehicle of Life and with it the Vital Heat and Spirits throughout the whole Body whereby it doth continually irrigate nourish and keep hot and supple all the Members Is it not admirable that from this Fountain of Life and Heat there should be Channels and Conduit-pipes to every even the least and most remote Part of the Body just as if from one Waterhouse there should be Pipes conveying the Water to every House in a Town and to every Room in each House or from one Fountain in a Garden there should be little Channels or Dikes cut to every Bed and every Plant growing therein as we have seen more than once done beyond the Seas I confess the Heart seems not to be designed to so noble an Use as is generally believed that is to be the Fountain or Conservatory of the vital Flame and to inspire the Blood therewith for the Lungs serve rather for the accension or maintaining that Flame the Blood receiving there from the Air those Particles which are one Part of the Pabulum or Fewel thereof and so impregnated running back to the Heart but to serve as a Machine to receive the Blood from the Veins and to force it out by the Arteries through the whole Body as a Syringe doth any Liquor though not by the same Artifice And yet this is no ignoble Use the continuance of the Circulation of the Blood being indispensibly necessary for the quickening and enlivening of all the Members of the Body and supplying of Matter to the Brain for the preparation of the Animal Spirits the Instruments of all Sense and Motion Now for this use of receiving and pumping out of the Blood the Heart is admirably contrived For First being a Muscular Part the Sides of it are composed of two orders of Fibres running circularly or spirally from Base to Tip contrarily one to the other and so being drawn or contracted contrary ways do violently constringe and straiten the Ventricles and strongly force out the Blood as we have formerly intimated Then the Vessels we call Arteries which carry from the Heart to the several Parts have Valves which open outwards like Trap-doors and give the Blood a free passage out of the Heart but will not suffer it to return back again thither and the Veins which bring it back from the several Members to the Heart have Valves or Trap-doors which open inwards so as to give way to the Blood to run into the Heart but prevent it from running back again that way Besides the Arteries consist of a quandruple Coat the Third of which is made up of annular or orbicular carneous Fibres to a good thickness and is of a Muscular Nature after every Pulse of the Heart serving to contract the Vessel successively with incredible celerity so by a kind of peristaltick Motion impelling the Blood onwards to the capillary Extremities and through the Muscles with great force and swiftness So the Pulse of the Arteries is not only caused by the pulsation of the Heart driving the Blood through them in manner of a Wave or Flush as Des Cartes and others would have it but by the Coats of the Arteries themselves which the experiments of a certain Lovain Physitian the first whereof is Galens do in my opinion make good against him First saith he if you slit the Artery and thrust into it a Pipe so big as to fill the Cavity of it and cast a strait ligature upon that part of the Artery containing the Pipe and so bind it fast to the Pipe notwithstanding the Blood hath free passage through the Pipe yet will not the Artery beat below the ligature but do but take off the ligature it will commence again to beat immediately But because one might be ready to reply to this Experiment that the reason why when bound it did not beat was because the current of the Blood being straitned by the Pipe when beneath the Pipe it came to have more liberty was not sufficient to stretch the Coats of the Artery and so cause a Pulse but when the ligature was taken off it might flow between the enclosed tube and the Coat of the Artery therefore he adds another which clearly evinces that this could not be the reason but that it is something flowing down the Coats of the Artery that causes the Pulse that is If you straiten the Artery never so much provided the sides of it do not quite meet and stop all passage of the Blood the Vessel will notwithstanding continue still to beat below or beyond the Coarctation So we see some Physitians both Ancient as Galen and Modern were of opinion that the Pulse of the Arteries was owing to their Coats though the first that I know of who observed the third Coat of an Artery to be a muscular Body composed of annulary Fibres was Dr. Willis The mention of the peristaltick Motion puts me in mind of an ocular Demonstration of it in the Gullet of Kine when they chew the Cud which I have often beheld with pleasure For after they have swallowed one morsel if you look stedfastly upon their Throat you will soon see another ascend and run pretty swiftly all along the Throat up to the Mouth which it could not do unless it were impelled by the successive contraction or peristaltick Motion of the Gullet continually following it And it is remarkable that these ruminant Creatures have a power by the imperium of their wills of directing this peristaltick Motion upwards or downwards I shall add no more concerning the Heart but that it and the Brain do mutuas operas tradere enable one another
no use of respiration by the Lungs the Blood doth not all I may say not the greatest part of it flow through them but there are two Passages or Channels contrived one called the foramen ovale by which part of the Blood brought by the vena cava passeth immediately into the left Ventricle of the Heart without entring the right at all the other is a large arterial Channel passing from the pulmonary Artery immediately into the Aorta or great Artery which likewise derives part of the Blood thither without running at all into the Lungs These two are closed up soon after the Child is born when it breaths no more as I may so say by the Placenta uterina but respiration by the Lungs is needful for it It is here to be noted that though the Lungs be formed so soon as the other Parts yet during the abode of the foetus in the Womb they lie by as useless In like manner I have observed that in ruminating Creatures the three formost Stomachs not only during the continuance of the Young in the Womb but so long as it is fed with Milk are unemployed and useless the Milk passing immediately into the fourth Another Observation I shall add concerning Generation which is of some moment because it takes away some concessions of Naturalists that give countenance to the Atheists fictitious and ridiculous Account of the first production of Mankind and other Animals viz. that all sorts of Insects yea and some Quadrupeds too as Frogs and Mice are produced Spontaneously My Observation and Affirmation is that there is no such thing in Nature as Aequivocal or Spontaneous Generation but that all Animals as well small as great not excluding the vilest and most contemptible Insect are generated by Animal Parents of the same Species with themselves that noble Italian Vertuoso Francesco Redi having experimented that no putrified Flesh which one would think were the most likely of any thing will of itself if all Insects be carefully kept from it produce any The same Experiment I remember Doctor Wilkins late Bishop of Chester told me had been made by some of the Royal Society No instance against this Opinion doth so much puzzle me as Worms bred in the Intestines of Man and other Animals But seeing the round Worms do manifestly generate and probably the other kinds too it 's likely they come originally from Seed which how it was brought into the Guts may afterwards possibly be discovered Moreover I am inclinable to believe that all Plants too that themselves produce Seed which are all but some very imperfect ones which scarce deserve the name of Plants come of Seeds themselves For that great Naturalist Malpighius to make experiment whether Earth would of its self put forth Plants took some purposely digged out of a deep Place and put it into a Glass Vessel the top whereof he covered with Silk many times doubled and strained over it which would admit the Water and Air to pass through but exclude the least Seed that might be wafted by the Wind the event was that no Plant at all sprang up in it nor need we wonder how in a Ditch Bank or Grass-Plat newly dig'd or in the Fenbanks in the Isle of Ely Mustard should abundantly spring up where in the Memory of Man none had been known to grow for it might come of Seed which had lain there more than a Mans Age. Some of the Ancients mentioning some Seeds that retain their fecundity Forty Years As for the Mustard that sprung up in the Isle of Ely though there never had been any in that Country yet might it have been brought down in the Channels by the Floods and so being thrown up the Banks together with the Earth might germinate and grow there From this Discourse concerning the Body of Man I shall make Three Practical Inferences First Let us give thanks to Almighty God for the Perfection and Integrity of our Bodies It would not be amiss to put it into the Eucharistical parr of our daily Devotions We praise thee O God for the due Number Shape and Use of our Limbs and Senses and in general of all the Parts of our Bodies we bless thee for the sound and healthful Constitution of them It is thou that hast made us and not we our selves in thy Book were all our Members written The Mother that bears the Child in her Womb is not conscious to any thing that is done there she understands no more how the Infant is formed than itself doth But if God hath bestowed upon us any peculiar Gift or Endowment wherein we excel others as Strength or Beauty or Activity we ought to give him special thanks for it but not to think the better of our selves therefore or despise them that want it Now because these Bodily Perfections being common Blessings we are apt not at all to consider them or not to set a just value on them and because the worth of things is best discerned by their want it would be useful sometimes to imagine or suppose our selves by some accident to be depriv'd of one of our Limbs or Senses as a Hand or a Foot or an Eye for then we cannot but be sensible that we should be in worse condition than now we are and that we should soon find a difference between two Hands and one Hand two Eyes and one Eye and that two excel one as much in worth as they do in number and yet if we could spare the use of the lost part the deformity and unsightlyness of such a defect in the Body would alone be very grievous to us Again which is less suppose we only that our Bodies want of their just magnitude or that they or any of our Members are crooked or distorted or disproportionate to the rest either in excess or defect nay which is least of all that the due motion of any one part be perverted as but of the Eyes in squinting the Eye-lids in twinkling the Tongue in stammering these things are such Blemishes and Offences to us by making us Gazing-stocks to others and Objects of their Scorn and Derision that we could be content to part with a good part of our Estates to repair such defects or heal such Infirmities These things considered and duly weighed would surely be a great and effectual motive to excite in us Gratitude for this Integrity of our Bodies and to esteem it no small blessing I say a blessing and favor of God to us for some there be that want it and why might not we have been of that number God was no way obliged to bestow it upon us And as we are to give thanks for the Integrity of our Body so are we likewise for the Health of it and the sound Temper and Constitution of all its Parts and Humors Health being the principal blessing of this Life without which we cannot enjoy or take comfort in any thing besides Neither are we to give thanks alone
account thereof from the necessary motion of Matter unguided by Mind for Ends prudently therefore break off their System there when they should come to Animals and so leave it altogether untoucht We acknowledg indeed there is a Posthumous piece extant imputed to Cartes and entituled De la formation du Foetus wherein there is some Pretence made to salve all this by fortuitous Mechanism But as the Theory thereof is built wholly upon a false supposition sufficiently confuted by our Harvey in his Book of Generation that the Seed doth materially enter into the composition of the Egg So is it all along precarious and exceptionable nor doth it extend at all to the differences that are in several Animals nor offer the least reason why an Animal of one Species might not be formed out of the Seed of another Thus far the Doctor with whom for the main I do consent I shall only add that Natural Philosophers when they endeavor to give an account of any of the Works of Nature by preconceived Principles of their own are for the most part grosly mistaken and confuted by Experience as Des Cartes in a matter that lay before him obvious to sense and infinitly more easie to find out the Cause of than to give an account of the Formation of the World that is the Pulse of the Heart which he attributes to an Ebullition and sudden expansion of the Blood in the Ventricles after the manner of Milk which being heated to such a Degree doth suddenly and as it were all at once flush up and run over the Vessel Whether this Ebullition be caused by a Nitro-Sulphureous ferment lodged especially in the left Ventricle of the Heart which mingling with the Blood excites such an Ebullition as we see made by the mixture of some Chymical Liquors viz. Oil of Vitriol and deliquated Salt of Tartar or by the vital flame warming and boyling the Blood But this conceit of his is contrary both to Reason and Experience For first It is altogether unreasonable to imagine and affirm that the cool venal Blood should be heated to so high a degree in so short a time as the interval of two Pulses which is less than the sixth part of a Minute Secondly In cold Animals as for Example Eels the Heart will beat for many hours after it is taken out of the Body yea tho the Ventricle be opened and all the Blood squeezed out Thirdly The process of the Fibres which compound the sides of the Ventricles running in Spiral Lines from the Tip to the Base of the Heart some one way and some the contrary do clearly shew that the Systole of the Heart is nothing but a Muscular constriction as a Purse is shut by drawing the Strings contrary ways Which is also confirm'd by Experience for if the Vertex of the Heart be cut off and a finger thrust up into one of the Ventricles in every Systole the Finger will be sensibly and manifestly pincht by the sides of the Ventricle But for a full Confutation of this Fancy I refer the Reader to Dr. Lower's Treatise de Corde Chap. 2. and his Rules concerning the transferring of Motion from one Body in motion to another are the most of them by Experience found to be false as they affirm which have made Trial of them This Pulse of the Heart Dr. Cudworth would have to be no Mechanical but a Vital motion which to me seems probable because it is not under the command of the Will nor are we conscious of any Power to cause or to restrain it but it is carried on and continued without our knowledge or notice neither can it be caused by the impulse of any external movent unless it be Heat But how can the Spirits agitated by Heat unguided by a vital Principle produce such a regular reciprocal motion If that Site which the Heart and its Fibres have in the Diastole be most natural to them as it seems to be why doth it again contract itself and not rest in that posture If it be once contracted in a Systole by the influx of the Spirits why the Spirits continually flowing in without let doth it not always remain so For the Systole seems to resemble the forcible bending of a Spring and the Diastole its flying out again to its natural site What is the Spring and principal Efficient of this Reciprocation What directs and moderates the motions of the Spirits They being but stupid and senseless matter cannot of themselves continue any regular and constant motion without the guidance and regulation of some intelligent Being You will say what Agent is it which you would have to effect this The sensitive Soul it cannot be because that is indivisible but the Heart when separated wholly from the Body in some Animals continues still to pulse for a considerable time nay when it hath quite ceased it may be brought to beat anew by the Application of warm Spittle or by pricking it gently with a Pin or Needle I answer it may be in these Instances the scattering Spirits remaining in the Heart may for a time being agitated by heat cause these faint Pulsations though I should rather attribute them to a plastick Nature or vital Principle as the Vegetation of Plants must also be But to proceed neither can I wholly acquiesce in the Hypothesis of that Honourable and deservedly famous Author I formerly had occasion to mention which I find in his free Enquiry into the vulgar Notion of Nature P. 77 78. delivered in these Words I think it probable that the great and wise Author of things did when he first formed the Universal and Undistinguished Matter into the World put its parts into various Motions whereby they were necessarily divided into numberless Portions of differing Bulks Figures and Situations in respect of each other And that by his infinite Wisdom and Power he did so guide and over-rule the motions of these Parts at the beginning of things as that whether in a shorter or a longer time Reason cannot determine they were finally disposed into that Beautiful and Orderly Frame that we call the World among whose Parts some were so curiously contrived as to be fit to become the Seeds or feminal Principles of Plants and Animals And I further conceive that he setled such Laws or Rules of local Motion among the parts of the Universal Matter that by his ordinary and preserving Concurse the several parts of the Universe thus once completed should be able to maintain the great Construction or System and Oeconomy of the mundane Bodies and propagate the Species of living Creatures The same Hypothesis he repeats again Pag. 124 125. of the same Treatise This Hypothesis I say I cannot fully acquiesce in because an intelligent Being seems to me requisite to execute the Laws of Motion For first Motion being a fluent thing and one part of its Duration being absolutely independent upon another it doth not follow that because any thing moves this moment
to work for first the Brain cannot itself Live unless it receive continual supplies of Blood from the Heart much less can it perform its functions of preparing and distributing the Animal Spirits nor the Heart Pulse unless it receives Spirits or something else that descends from the Brain by the Nerves For do but cut asunder the Nerves that go from the Brain to the Heart the motion thereof in more perfect and hot Creatures ceaseth immediately Which Part began this round is the Question Eighthly The next Part I shall treat of shall be the Hand this 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 or superlative Instrument which serves us for such a multitude of Uses as it is not easie to enumerate whereto if we consider the Make and Structure of it we shall find it wonderfully adapted First it is divided into Four Fingers bending forward and one opposite to them bending backwards and of greater strength than any of them singly which we call the Thumb to joyn with them severally or united whereby it is fitted to lay hold of objects of any size or quantity The least things as any small single Seed are taken up by the Thumb and Forefinger those a little greater by the Thumb and two Fingers which also we chiefly employ to manage the Needle in Sewing and the Pen in Writing When we would take up a greater quantity of any thing we make use of the Thumb and all the Fingers Sometimes we use one Finger only as in póinting at any thing picking things out of holes or long and narrow Vessels sometimes all severally at one time as in stopping the strings when we play upon any musical Instrument 2. The Fingers are strengthened with several Bones jointed together for motion and furnished with several Muscles and Tendons like so many Pullies to bend them circularly forward which is most convenient for the firm holding and griping of any Object Which of how great constant and necessary Use it is in pulling or drawing but especially in taking up and retaining any sort of Tool or Instrument to work withal in Husbandry and all mechanick Arts is so obvious to every mans Observation that I need not spend time to instance in particulars Moreover the several Fingers are furnished with several Muscles to extend and open the Hand and to move them to the Right and Left and so this Division and Motion of the Fingers doth not hinder but that the whole Hand may be employed as if it were all of a piece as we see it is either expanded as in striking out smoothing and folding up of Cloths and some mechanick Uses or contracted as in Fighting Kneading of Dough and the like It is also notable and indeed wonderful that the Tendons bending the middle Joint of the Fingers should be perforated to give passage to the Tendons of the Muscles which draw the uppermost Joynts and all bound down close to the Bone with strong Fillets lest they should start up and hinder the Hand in its work standing like so many Bowstrings 3. The Fingers ends are strengthened with Nails as we fortifie the ends of our Staves or Forks with Iron Hoops or Ferules which Nails serve not only for defence but for ornament and many Uses The Skin upon our Fingers ends is thin and of most exquisite Sense to help us to judg of any thing we handle If now I should go about to reckon up the several Uses of this Instrument Time would sooner fail me then Matter By the help of this we do all our Works we Build our selves Houses to dwell in we make our selves Garments to wear we Plow and Sow our Grounds with Corn Dress and Cultivate our Vineyards Gardens and Orchards gather and lay up our Grain and Fruits we prepare and make ready our Victuals Spinning Weaving Painting Carving Engraving and that Divinely invented Art of Writing whereby we transmit our own Thoughts to Posterity and converse with and participate the Observations and Inventions of them that are long ago Dead all performed by this This is the only Instrument for all Arts whatsoever no improvement to be made of any experimental Knowledg without it Hence as Aristotle saith well they do amiss that complain that Man is worse dealt with by Nature than other Creatures whereas they have some Hair some Shels some Wool some Feathers some Scales to defend themselves from the injuries of the Weather Man alone is Born Naked and without all covering Whereas they have natural Weapons to defend themselves and offend their Enemies some Horns some Hoofs some Teeth some Talons some Claws some Spurs and Beaks Man hath none of all these but is weak and feeble and unarmed sent into the World Why a Hand with Reason to use it supplies the Uses of all these that 's both a Horn and a Hoof and a Talon and a Tusk c. because it enables us to use Weapons of these and other Fashions as Swords and Spears and Guns Besides this advantage a Man hath of them that whereas they cannot at pleasure change their coverings or lay aside their Weapons or make use of others as occasion serves but must abide Winter and Summer Night and Day with the same Cloathing on their Backs and sleep with their Weapons upon them a Man can alter his Cloathing according to the exigency of the Weather go warm in Winter and cool in Summer cover up himself hot in the Night and lay aside his Cloaths in the Day and put on or off more or fewer according as his Work and Exercise is and can as occasion requires make use of divers sorts of Weapons and choice of such at all turns as are most proper and convenient whereby we are enabled to subdue and rule over all other Creatures and use for our own behoof those Qualities wherein they excel as the Strength of the Ox the Valor and Swiftness of the Horse the Sagacity and Vigilancy of the Dog and so make them as it were our own Had we wanted this Member in our Bodies we must have lived the Life of Brutes without House or Shelter but what the Woods and Rocks would have afforded without Cloths or Covering without Corn or Wine or Oil or any other Drink but Water without the warmth and comfort or other uses of Fire and so without any Artificial Bak'd Boil'd or Roast Meats but must have scrambled with the wild Beasts for Crabs and Nuts and Akhorns and Sallets and such other things as the Earth puts forth of her own accord We had lain open and exposed to Injuries and had been unable to resist or defend our selves against almost the weakest Creature The remaining Parts I shall but briefly run over That the Back-bone should be divided into so many Vertebres for commodious bending and not be one entire rigid Bone which being of that length would have been often in danger of snapping in sunder That the several Vertebres should be so Elegantly and Artificially compacted and joined together that they