Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667

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            <p type="main">
              <s>
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              it will paſſe any further, or elſe that there it would immediately
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              ſtand ſtill, and move no further?</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>I believe that it would continue to move a great way
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              further.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>But this motion beyond the centre, would it not be
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              wards, and according to your aſſertion preternatural, and violent?
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              </s>
              <s>And yet on what other principle do you make it to depend, but
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              only upon the ſelf ſame, which did carry the ball to the centre,
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              and which you called intrinſecal, and natural? </s>
              <s>Finde, if you can,
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              another external projicient, that overtaketh it again to drive it
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              upwards. </s>
              <s>And this that hath been ſaid of the motion thorow
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              the centre, is alſo ſeen by us here above; for the interne
                <emph type="italics"/>
              impetus
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                <lb/>
                <arrow.to.target n="marg418"/>
                <lb/>
              of a grave body falling along a declining ſuperficies, if the ſaid
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              ſuperficies be reflected the other way, it ſhall carry it, without a
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              jot interrupting the motion, alſo upwards. </s>
              <s>A ball of lead that
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              hangeth by a thread, being removed from its perpendicularity,
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              ſcendeth ſpontaneouſly, as being drawn by its internal inclination,
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              and without any interpoſure of reſt, paſſeth beyond the loweſt
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              point of perpendicularity: and without any additional mover,
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              moveth upwards. </s>
              <s>I know that you will not deny, but that the
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              principle of grave bodies that moveth them downwards, is no leſs
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              natural, and intrinſecal, than that principle of light bodies, which
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              moveth them upwards: ſo that I propoſe to your conſideration a
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              ball of lead, which deſcending through the Air from a great
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              titude, and ſo moving by an intern principle, and comming to a
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              depth of water, continueth its deſcent, and without any other
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              terne mover, ſubmergeth a great way; and yet the motion of
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              deſcent in the water is preternatural unto it; but yet nevertheleſs
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              dependeth on a principle that is internal, and not external to the
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              ball. </s>
              <s>You ſee it demonſtrated then, that a moveable may be
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              moved by one and the ſame internal principle, with contrary
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              tions.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg418"/>
                <emph type="italics"/>
              The natural
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              tion changeth it
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              ſelfe into that
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              which is called
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              ternatural and
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              olent.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>I believe there are ſolutions to all theſe objections,
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              though for the preſent I do not remember them; but however it
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              be, the Author continueth to demand, on what principle this
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              cular motion of grave and light bodies dependeth; that is,
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              ther on a principle internal, or external; and proceeding
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              wards, ſheweth, that it can be neither on the one, nor on the other,
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              ſaying;
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              Si ab externo; Deuſne illum excitat per continuum
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              culum? </s>
              <s>an verò Angelus, an aër? </s>
              <s>Et hunc quidem multi
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              nant. </s>
              <s>Sed contra----[In Engliſh thus]
                <emph.end type="italics"/>
              If from an externe
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              ciple; Whether God doth not excite it by a continued Miracle?
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              </s>
              <s>or an Angel, or the Air? </s>
              <s>And indeed many do aſſign this. </s>
              <s>But
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              on the contrary-----.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>Trouble not your ſelf to read his argument; for I am </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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