Galilei, Galileo, Discourse concerning the natation of bodies, 1663

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              <s>
                <pb pagenum="441"/>
              tion is not inferiour; whereupon, we muſt of neceſſity conclude
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              that it is nothing: becanſe, if it were of any ſenſible power, ſome
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              large Plate might be found or compounded of a Matter alike in
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              vity to the water, which not only would ſtay between the two
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              ters; but, moreover, ſhould not be able to deſcend or aſcend
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              out notable force. </s>
              <s>We may likewiſe collect the ſame from an
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                <arrow.to.target n="marg1491"/>
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              ther Experiment, ſhewing that the Water gives way alſo in the ſame
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              manner to tranſverſall Diviſion; for if in a ſetled and ſtanding water
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              we ſhould place any great Maſs that goeth not to the bottom,
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              ing it with a ſingle (Womans) Hair, we might carry it from place to
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              place without any oppoſition, and this whatever Figure it hath,
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              though that it poſſeſs a great ſpace of water, as for inſtance, a great
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              Beam would do moved ſide-ways. </s>
              <s>Perhaps ſome might oppoſe me
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              and ſay, that if the Reſiſtance of water againſt Diviſion, as I affirm,
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              were nothing; Ships ſhould not need ſuch a force of Oars and Sayles
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              for the moving of them from place to place in a tranquile Sea, or
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              ſtanding Lake. </s>
              <s>To him that ſhould make ſuch an objection, I would
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              reply, that the water contraſteth not againſt, nor ſimply reſiſteth
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              Diviſion, but a ſudden Diviſion, and with ſo much greater
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              tence, by how much greater the Velocity is: and the Cauſe of this
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              Reſiſtance depends not on Craſſitude, or any other thing that
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              lutely oppoſeth Diviſion, but becauſe that the parts of the water
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              divided, in giving way to that Solid that is moved in it, are
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              ſelves alſo neceſſitated locally to move, ſome to the one ſide, and ſome
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              to the other, and ſome downwards: and this muſt no leſs be done
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              by the waves before the Ship, or other Body ſwimming through the
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              water, than by the poſteriour and ſubſequent; becauſe, the Ship
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              proceeding forwards, to make it ſelf a way to receive its Bulk, it is
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              requiſite, that with the Prow it repulſe the adjacent parts of the
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              water, as well on one hand as on the other, and that it move them
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              as much tranſverſly, as is the half of the breadth of the Hull: and
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              the like removall muſt thoſe waves make, that ſucceeding the Poump
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              do run from the remoter parts of the Ship towards thoſe of the
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              middle, ſucceſſively to repleniſh the places, which the Ship in
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              vancing forwards, goeth, leaving vacant. </s>
              <s>Now, becauſe, all
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                <arrow.to.target n="marg1493"/>
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              tions are made in Time, and the longer in greater time: and it being
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              moreover true, that thoſe Bodies that in a certain time are moved
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              by a certain power ſuch a certain ſpace, ſhall not be moved the ſame
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              ſpace, and in a ſhorter Time, unleſs by a greater Power: therefore,
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              the broader Ships move ſlower than the narrower, being put on by
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              an equall Force: and the ſame Veſſel requires ſo much greater
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              force of Wind, or Oars, the faſter it is to move.</s>
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          </chap>
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    </archimedes>
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