Galilei, Galileo, The systems of the world, 1661

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="065/01/136.jpg" pagenum="128"/>
              tarding, as being contrary to nature; and would be longer or
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              ſhorter, according to the greater or leſs impulſe, and according to
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              the greater or leſs acclivity.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>It ſeems, then, that hitherto you have explained to me
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              the accidents of a moveable upon two different Planes; and that
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              in the inclining plane, the grave moveable doth ſpontaneouſly
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              ſcend, and goeth continually accelerating, and that to retain it in
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              reſt, force muſt be uſed therein: but that on the aſcending plane,
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              there is required a force to thruſt it forward, and alſo to ſtay it in
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              reſt, and that the motion impreſſed goeth continually diminiſhing,
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              till that in the end it cometh to nothing. </s>
              <s>You ſay yet farther,
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              that in both the one and the other caſe, there do ariſe differences
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              from the planes having a greater or leſs declivity or acclivity; ſo
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              that the greater inclination is attended with the greater velocity;
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              and contrariwiſe, upon the aſcending plane, the ſame moveable
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              thrown with the ſame force, moveth a greater diſtance, by how
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              much the elevation is leſs. </s>
              <s>Now tell me, what would befall the
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              ſame moveable upon a ſuperficies that had neither acclivity nor
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              declivity?</s>
            </p>
            <p type="main">
              <s>SIMPL. </s>
              <s>Here you muſt give me a little time to conſider of an
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              anſwer. </s>
              <s>There being no declivity, there can be no natural
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              nation to motion: and there being no acclivity, there can be no
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              reſiſtance to being moved; ſo that there would ariſe an
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              rence between propenſion and reſiſtance of motion; therefore,
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              methinks it ought naturally to ſtand ſtill. </s>
              <s>But I had forgot my
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              ſelf: it was but even now that
                <emph type="italics"/>
              Sagredus
                <emph.end type="italics"/>
              gave me to underſtand
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              that it would ſo do.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>So I think, provided one did lay it down gently: but
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              if it had an
                <emph type="italics"/>
              impetus
                <emph.end type="italics"/>
              given it towards any part, what would
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              low?</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>There would follow, that it ſhould move towards that
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              part.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>But with what kind of motion? </s>
              <s>with the continually
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              accelerated, as in declining planes; or with the ſucceſſively
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              tarded, as in thoſe aſcending.</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>I cannot tell how to diſcover any cauſe of acceleration,
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              or retardation, there being no declivity or acclivity.</s>
            </p>
            <p type="main">
              <s>SALV. Well: but if there be no cauſe of retardation, much
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              leſs ought there to be any cauſe of reſt. </s>
              <s>How long therefore
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              would you have the moveable to move?</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>As long as that ſuperficies, neither inclined nor
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              ned ſhall laſt.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>Therefore if ſuch a ſpace were interminate, the motion
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              upon the ſame would likewiſe have no termination, that is, would
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              be perpetual.</s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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