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

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb pagenum="428"/>
              and, furthermore, not with every Matter, but with thoſe
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              wherewith it may be able ro execute the deſired operation. </s>
              <s>
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              as we ſee it verified by Experience, that the Acute and ſharp Angle
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              more apt to cut, than the Obtuſe; yet alwaies provided, that
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              the one and the other, be joyned with a Matter apt to cut, as
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              example, with Steel. </s>
              <s>Therefore, a Knife with a fine and
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              edge, cuts Bread or Wood with much eaſe, which it will not do,
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              the edge be blunt and thick: but he that will inſtead of Steel,
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              Wax, and mould it into a Knife, undoubtedly ſhall never know
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              effects of ſharp and blunt edges: becauſe neither of them will
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              the Wax being unable by reaſon of its flexibility, to overcome
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              hardneſs of the Wood and Bread. </s>
              <s>And, therefore, applying
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              like diſcourſe to our purpoſe, they ſay, that the difference of Figure
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              will ſhew different effects, touching Natation and Submerſion,
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              not conjoyned with any kind of Matter, but only with thoſe
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              which, by their Gravity, are apt to reſiſt the Velocity of the
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              whence he that would elect for the Matter, Cork or other light
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              unable, through its Levity, to ſuperate the Craſſitude of the
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              and of that Matter ſhould forme Solids of divers Figures, woulld
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              vain ſeek to find out what operation Figure hath in Natation or
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              merſion; becauſe all would ſwim, and that not through any property
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              of this or that Figure, but through the debility of the Matter,
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              ing ſo much Gravity, as is requiſite to ſuperate and overcome the
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              Denſity and Craſſitude of the water.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg1459"/>
              An objection
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              gainſt the
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              riment in Wax.</s>
            </p>
            <p type="main">
              <s>Its needfull, therefore, if wee would ſee the effect wrought by
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              Diverſity of Figure, firſt to make choice of a Matter of its
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              apt to penetrate the Craſſitude of the water. </s>
              <s>And, for this
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                <arrow.to.target n="marg1460"/>
                <lb/>
              they have made choice of ſuch a Matter, as fit, that being readily
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              duced into Sphericall Figure, goes to the Bottom; and it is Ebony
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              of which they afterwards making a ſmall Board or Splinter, as thin
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              a Lath, have illuſtrated how that this, put upon the Surface of the
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              water, reſts there without deſcending to the Bottom: and making, on
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              the otherſide, of the ſame wood a Ball, no leſs than a hazell Nut,
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              they ſhew, that this ſwims not, but deſcendes. </s>
              <s>From which
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              ment, they think they may frankly conclude, that the Breadth ofthe
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              Figure in the flat Lath or Board, is the cauſe of its not deſcendingto
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              the Bottom, foraſmuch as a Ball of the ſame Matter, not
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              from the Board in any thing but in Figure, ſubmergeth in the
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              water to the Bottom. </s>
              <s>The diſcourſe and the Experiment hath
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              ſo much of probability and likely hood of truth in it, that it would be
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              no wonder, if many perſwaded by a certain curſory
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              ſhould yield credit to it; nevertheleſs, I think I am able to diſcover,
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              how that it is not free from falacy.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg1460"/>
              An
                <lb/>
              ment in Ebany,
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              brought to
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              prove the
                <lb/>
              timent in Wax.</s>
            </p>
            <p type="main">
              <s>Beginning, therefore, to examine one by one, all the particulars </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>