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it, but only in this direction; yet does he himself confefs, that because these two Motions of the Earth, the Annual and Diurnal, would be inuch more conveniently made upon parallel Axes, therefore, according to the Laws of Mechanifm, they fhould 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 pafs, fo neither hath there been for thefe laft two Thousand Years (according to the best Obfervations and Judg ments of Aftronomers) 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 refolvable into nothing but a final and mental Caufe, or the Baso, because it was beft it fhould be fo, the variety of the Seafons of the Year depending thereupon. But the greatest of all the particular Phanomena, is the Formation and Organization of the Bodies of Animals, confifting of fuch variety and curiofity, that these mechanick Philofophers being no way able to give an account thereof from the neceffary Motion of Matter, unguided by Mind for Ends, prudently therefore break off their Syftem there, when they should come to Animals, and fo leave it altogether untouch'd. We acknowledge indeed. there is a Pofthumous Piece extant, imputed to Cartes, and entituled, De la formation du Foetus, wherein there is fome Pretence made to falve all this fortuitous Mechanifin. But as the Theory thereof is built wholly upon a falfe Suppo

fition,

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fition, fufficiently confuted by our Harvey in his Book of Generation, that the Seed doth materially enter into the Compofition of the Egg; fo is it all along precarious and exceptionable: Nor doth it extend at all to Differences that are in feveral Animals, nor offer the least reason why an Animal of one Species might not be form'd out of the Seed of another. Thus far the Dr. with whom for the main I do confent. I fhall 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 mista ken and confuted by Experience; as Des Cartes in a Matter that lay before him, obvious to Senfe, and infinitely more eafie to find out the Caufe of, than to give an account of the Formation of the World; that is the Pulfe of the Heart, which he attributes to an Ebullition and fudden Expanfion of the Blood in its Ventricles, after the manner of the Milk, which being heated, to fuch a degree, doth fuddenly, and as it were all at once, flush up and run over the Veffel. 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 fuch an Ebullition, as we fee made by the mixture. of fome Chymical Liquors, viz. Oil of Vitriol, and deliquated Salt of Tartar; or by the vital Flame warming and boiling the Blood. But this Conceit of his is contrary both to Reafon and Experience: For, firft, 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 fo fhort a time as the Interval of two Pulfes, which is less than the fixth 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 open'd, and all the Blood fqueez'd out Thirdly, The Procefs of the Fibres which com pound the fides of the Ventricles running in Spiral Lines from the Tip to the Base of the Heart, fome one way, and fome the contrary, do clearly fhew that the Syftole of the Heart is nothing but a Mufcular conftriction, 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 fenfibly and manifeftly pinch'd by the fides of the Ventricle. But for a full confutation of this Fancy, I refer the Reader to Dr. Lower's Treatife 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 reft, are the moft of them by Experience found to be false; as they affirm who have made Trial of them.

This Pulfe 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 confcious of any Power to caufe or to restrain it, but it is carried on and continued without our knowledge

knowledge or notice; neither can it be caused by the impulfe of any external Movent, unless it be Heat. But how can the Spirit agitated by Heat, unguided by a vital Principle, produce fuch a regu lar 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 it felf, and not reft in that pofture? If it be once contracted in a Softole by the influx of the Spirits, why, the Spirits continually flowing in without let, doth it not always remain fo? [for the Systole feems to resemble the forcible bending of a Spring, and the Diaf tole its flying out again to its natural fite.] What is the Spring and principal Efficient of this Reciprocation? What directs and moderates the Motions of the Spirits? They being but ftupid and fenfelefs matter, cannot of themselves continue any regular and conftant motion, without the guidance and regulation of fome intelligent Being. You will fay, What Agent is it which you would have to effect this? The fenfitive Soul it cannot be, because, that is indivifible, but the Heart when feparated wholly from the Body in fome Animals, continues ftill to pulfe for a confiderable time; nay when it hath quite ceas'd, it may be brought to beat a-new by the Application of warm Spittle, or by pricking it gently with a Pin or Needle. I anfwer, it may be in these Inftances, the fcattering Spirits remaining in the Heart, may for a time, being agitated by heat, caufe thefe faint Pulfations; tho' I should rather attribute them to a plastick

Nature

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Nature or Vital Principle, as the Vegetation of Plants must also be.

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But, to proceed, neither can I wholly ac quiefce in the Hypothefis of that Honourable and defervedly Famous Author, I formerly had occafion to mention, which I find in his free inquiry into the Vulgar Notion of Nature, p. 77, 78. deliver'd in thefe words. "I think it probable, "that the great and wife Author of things did, ແ when he firft form'd the Universe and undiftinguish'd Matter into the world, put its parts "into various Motions, whereby they were neceffarily divided into numberlefs Portions of differing Bulks, Figures and Situations, in refpect of each other: And that by his infinite "Wisdom and Power he did fo guide and over"rule the Motions of these Parts, at the beginning of things, as that (whether in a fhorter or a longer time Reafon cannot determine) they were finally difpos'd into that beautiful "and orderly Frame that we call the World;

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among whose Parts fome were fo curioufly "contriv'd, as to be fit to become the Seeds or "feminal Principles of Plants and Animals "And I further conceive, that he fettled fuch Laws or Rules of local Motion among the parts of the Univerfal Matter, that by his or dinary and preferving Concourfe, the feveral parts of the Universe thus once compleated, "fhould be able to maintain the great Con"ftruction or System and Oeconomy of the • Mundane Bodies, and propagate the Species "of living Creatures" The fame Hypothefis he

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repeats

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