Page:Discourse Concerning the Natation of Bodies.djvu/45

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Natation Of Bodies
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divisions, they cannot receive them, but only from acuter Divisors than Fire; but a Stick or Rod of Iron, moved in the melted Met all, is not such a one. Water consists of parts that admit of no farther division.Of a like Constitution and Consistence, I account the parts of Water, and other Liquids to be, namely, incapable of Division by reason of their Tenuity; or if not absolutely indivisible, yet at least not to be divided by a Board, or other Solid Body, palpable unto the band, the Sector being alwayes required to be more sharp than the Solid to be cut. Solids dimitted into the water, do onely move, and not divide it.Solid Bodies, therefore, do only move, and not divide the Water, when put into it; whose parts being before divided to the extreamest minuity, and therefore capable of being moved, either many of them at once, or few, or very few, they soon give place to every small Corpuscle, that descends in the same: for that, it being little and light, descending in the Air, and arriving to the Surface of the Water, it meets with Particles of Water more small, and of less Resistance against Motion and Extrusion, than is its own prement and extrusive force, whereupon it submergeth, and moveth such a portion of them, as is proportionate to its Power. There is not, therefore, any Resistance in Water against Division, nay, there is not in it any divisible parts. If there were any Resistance of Division in water, it must needs be small, in that it is overcome by an Hair, a Grain of Lead, or a slight bathing of the Solid.I adde, moreover, that in case yet there should be any small Resistance found (which is absolutely false) haply in attempting with an Hair to move a very great natant Machine, or in essaying by the addition of one small Grain of Lead to sink, or by removall of it to raise a very broad Plate of Matter, equall in Gravity with Water, (which likewise will not happen, in case we proceed with dexterity) we may observe that that Resistance is a very different thing from that which the Adversaries produce for the Cause of the Natation of the Plate of Lead or Board of Ebony, for that one may make a Board of Ebony, which being put upon the Water swimmeth, and cannot be submerged, no not by the addition of an hundred Grains of Lead put upon the same, and afterwards being bathed, not only sinks, though the said Lead be taken away, but though moreover a quantity of Cork, or of some other light Body fastened to it, sufficeth not to hinder it from sinking unto the bottome: so that you see, that although it were granted that there is a certain small Resistance of Division found in the substance of the Water, yet this hath nothing to do with that Cause which supports the Board above the Water, with a Resistance an hundred times greater than that which men can find in the parts of the Water: The uper parts of the Water, do no more resist Division than the middle or lower parts.nor let them tell me, that only the Surface of the Water hath such Resistance, and not the internall parts, or that such Resistance is found greatest in the beginning of the Submersion, as it also seems that in the beginning, Motion meets with greater opposition, than in the continuance of it; because, first, Waters Resistance of division, not greater in the beginning of the Submersion.I will permit, that the Water be stirred, and that the superiour parts be mingled with the middle, and inferiour parts, or that those above be wholly removed, and those in the middle only made use off, and yet you shall see the effect for

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