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

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb pagenum="429"/>
              have been produced, I ſay, that Figures, as ſimple Figures, not only
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                <arrow.to.target n="marg1461"/>
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              operate not in naturall things, but neither are they ever ſeperated
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              from the Corporeall ſubſtance: nor have I ever alledged them ſtript
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              of ſenſible Matter, like as alſo I freely admit, that in our
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              ing to examine the Diverſity of Accidents, dependant upon the
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              riety of Figures, it is neceſſary to apply them to Matters, which
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              ſtruct not the various operations of thoſe various Figures: and I
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              mit and grant, that I ſhould do very ill, if I would experiment the
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              fluence of Acuteneſſe of edge with a Knife of Wax, applying it to cut
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              an Oak, becauſe there is no Acuteneſs in Wax able to cut that
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              very hard wood. </s>
              <s>But yet ſuch an Experiment of this Knife, would
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              not be beſides the purpoſe, to cut curded Milk, or other very yielding
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              Matter: yea, in ſuch like Matters, the Wax is more commodious
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              than Steel; for finding the diverſity depending upon Angles, more or
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              leſs Acute, for that Milk is indifferently cut with a Raiſor, and with
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              a Knife, that hath a blunt edge. </s>
              <s>It needs, therefore, that regard be
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              had, not only to the hardneſs, ſolidity or Gravity of Bodies, which
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              under divers figures, are to divide and penetrate ſome Matters, but it
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              forceth alſo, that regard be had, on the other ſide, to the Reſiſtance
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              of the Matters, to be divided and penetrated. </s>
              <s>But ſince I have in
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              making the Experiment concerning our Conteſt, choſen a Matter
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              which penetrates the Reſiſtance of the water; and in all figures
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              cendes to the Bottome, the Adverſaries can charge me with no defect;
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              yea, I have propounded ſo much a more excellent Method than they,
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              in as much as I have removed all other Cauſes, of deſcending or
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              not deſcending to the Bottom, and retained the only ſole and pure
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              variety of Figures, demonſtrating that the ſame Figures all deſcende
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              with the only alteration of a Grain in weight: which Grain being
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              removed, they return to float and ſwim; it is not true, therefore,
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              (reſuming the Example by them introduced) that I have gon about
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              to experiment the efficacy of Acuteneſs, in cutting with Matters
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              able to cut, but with Matters proportioned to our occaſion; ſince
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              they are ſubjected to no other variety, then that alone which depends
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              on the Figure more or leſs a
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                <arrow.to.target n="marg1462"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg1461"/>
              Figure is
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              ſeperable from
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              Corporeall
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              ſtance.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg1462"/>
              The anſwer to
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              the Objection
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              gainſt the
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              riment of the
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              Wax.</s>
            </p>
            <p type="main">
              <s>But let us proceed a little farther, and obſerve, how that indeed
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              the Conſideration, which, they ſay, ought to be had about the Election
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              of the Matter, to the end, that it may be proportionate for the
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              king of our experiment, is needleſly introduced, declaring by the
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              ample of Cutting, that like as Acuteneſs is inſufficient to cut, unleſs
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              when it is in a Matter hard and apt to ſuperate the Reſiſtance of the
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              wood or other Matter, which we intend to cut; ſo the aptitude of
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              deſcending or notdeſcending in water, ought and can only be known
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              in thoſe Matters, that are able to overcome the Renitence, and
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              rate the Craſſitude of the water. </s>
              <s>Unto which, I ſay, that to make
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              diſtinction and election, more of this than of that Matter, on which to </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>