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it, but only in this direction; yet does he himself confess, that because these two Motions of the Earth, the Annual and Diurnal, would be inuch more conveniently inade upon parallel Axes, therefore, according to the Laws of Mechanisın, they should be perpetually brought nearer and nearer together, 'till at length the Equator and Ecliptick come to have their Axis parallel, which as it hath not yet come to pass, lo neither hath there been for these last two Thousand Years (according to the best Observations and Judgînents of Astronomers) any nearer approach made of them one to another.' Wherefore the Continuation of these two Motions of the Earth, the Annual and Diurnal, upon Axes not parallel, is resolvable into nothing but a final and mental Cause, or the cò Beansov, because it was best it should be so, the variety of the Seasons of the Year depending thereupon. But the greatest of all the particular Phenomena, is the Formation and Organization of the Bodies of Animals, confisting of such variety and curiosity, that these mechanick Philosophers being no way able to give an account thereof from the necessary Motion of Matter, unguided by Mind for Ends, pru-' dently therefore break off their System there, when they should come to Animals, and so leave it altogether untouch'd. We acknowledge indeed there is a Pofthumous Piece extant, imputed to Cartes, and ëntituled, De la formation du Fætus, wherein there is some Pretence made to falve all this fortuitous Mechanisın. But as the Theory thereof is built wholly upon a false Şuppo ..


sition, sufficiently confuted by our Harvey in
his Book of Generation, that the Seed dotb ma-
terially enter into the Composition of the Egg; so
is it all along precarious and exceptionable : Nor
doth it extend at all to Differences that are in
several Animals, nor offer the least reason why
an Animal of one Species might not be formd
out of the Seed of another. Thus far the Dr.
with whom for tlie main I do consent. I shall
only add, that Natural Philofophers, when
they endeavour to give an account of any of
the Works of Nature by preconceiv'd Principles
of their own, are for the most part grofly inista-
ken and confuted by Experience; as Des Car-
tes in a Matter that lay before him, obvious to
Sense, and infinitely 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 Expanfion of the Blood in its Ven-
tricles, after the manner of the Milk, which
being heated to such a degree, doth fuddenly,
and as it were all at once, flush up and run o-
ver the Vessel. Whether this Ebullition be
caus'd by a Nitro-Sulphureous Ferment lodg'd
especially in the left Ventricle of the Heart,
which mingling with the Blood, excites such
an Ebullition, as we see inade by the mixture
of some Chymical Liquors, viz. Oil of Vic
triol, and deliquated Sålt of Tartar; or by the .
vital Flame warming and boiling the Blood.
But this Conceit of his is contrary both to Rea-
fon and Experience : For, first, it is altogether


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unreasonable to imagine and affirm that the cool venal Blood should be heated to fo high a degree in so short a time as the Interval of two Pusses, which is less than the fixth part of a Minutes 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 open'd, and all the Blood squeez'd outi Thirdly, The Process of the Fibres which com

Spiral Lines from the Tip to the Base of the Heart, fome 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 fhut 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 maniféftly pinch'd 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 Des Cartes's Rules concerning the transferring of Motion from one Body in motion to another in motion or in rest, are the most of them by Experience found to be false; as they affirm who have made Trial of thein.

This Pulse of the Heart Dr. Cidrworth would have to be 110 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 knotyledge or notice; neither can it be caused by theiinpulse of any external Movent, unless it be Heat." But how can the Spirit agitated by Heat, unguided by a vital Principle, produce such a regur İar reciprocalMotion? 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 it félf, 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 renuin fo ? [for the Systole seems to resemble the forcible bending of a Spring, and the Diaf tole its flying out again to its natural site. 7 What

ciprocation What directs and moderates the Motions of the Spirits ? They being but stupid and senselefs inatter: cannot of themselves continue any regular and constant motioii, without the guidance and regulation of fome 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 ceas'd, it may be brought to beat a-riew by the Application of warm Spittle, or by pricking it ģently with a Pin or Needle.' I answer, it may be in these Instances, the scattering Spirits remaining in the Heart, inay for a time, being agitated by heat, cause these faint Pulsations; tho? 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 defervedly Famous Author, I formerly had occa fion to mention, which I find in his free inquiry into the Vulgar Notion of Nature, p. 77, 78. deliver'd in these words. “ I think it probable, " that the great and wife Author of things did, " when he first form'd the Universe and urdi“ ftinguish'd Matter into the world, put its parts “ into various Motions, whereby they were ne

cessarily divided into numberless Portions of “ differing Bulks, Figures and Situations, in res “ fpect 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 begin “ ning of things, as that (whether in a shorter “ or a longer time Reason cannot determine) “ they were finally dispos'd into that beautiful “" and orderly Frame that we call the World ; “ among whole Parts some were so curiously « contrivd, as to be fit to becoine the Seeds or “ feminal Principles of Plants and Animals: " And I further conceive, that he settled such

Laws or Rules of local Motion among the “ parts of the Universal Matter, that by his ors dinary and preserving Concourse, the several " parts of the Universe thus once compleated, < should be able to maintain the great Cons “ struction or System and Oeconomy of the " Mundane Bodies, and propagate the Species “ of living Creatures”. The same Hypothefis he


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