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

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      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="040/01/164.jpg" pagenum="146"/>
              Tower. </s>
              <s>And this is the cauſe why the right motion made along
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              the ſide of the Tower appeareth to us more and more accelerate.
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              </s>
              <s>It appeareth alſo, how by reaſon of the infinite acuteneſſe of
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              the contact of thoſe two circles D C, C I, the receſſion of the
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              cadent moveable from the circumference C F D; namely, from
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              the top of the Tower, is towards the beginning extream ſmall,
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              which is as much as if one ſaid its motion downwards is very ſlow,
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              and more and more ſlow
                <emph type="italics"/>
              in infinitum,
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              according to its vicinity to
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              the term C, that is to the ſtate of reſt. </s>
              <s>And laſtly it is ſeen how
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              in the end this ſame motion goeth to terminate in the centre of the
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              Earth A.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg329"/>
                <emph type="italics"/>
              The line
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              bed by a moveable
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              in its natural
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              ſcent, the motion
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              of the Earth
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              bout its own centre
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              being preſuppoſed,
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              would probably be
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              the circumference
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              of a circle.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>I underſtand all this very well, nor can I perſwade my
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              ſelf that the falling moveable doth deſcribe with the centre of its
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              gravity any other line, but ſuch an one as this.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>But ſtay a little
                <emph type="italics"/>
              Sagredus,
                <emph.end type="italics"/>
              for I am to acquaint you
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              alſo with three Obſervations of mine, that its poſſible will not
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                <arrow.to.target n="marg330"/>
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              pleaſe you. </s>
              <s>The firſt of which is, that if we do well conſider, the
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              moveable moveth not really with any more than onely one motion
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              ſimply circular, as when being placed upon the Tower, it moved
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              with one ſingle and circular motion. </s>
              <s>The ſecond is yet more
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                <arrow.to.target n="marg331"/>
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              ſant; for, it moveth neither more nor leſſe then if it had ſtaid
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              tinually upon the Tower, being that to the arches C F, F G, G H,
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              &c. </s>
              <s>that it would have paſſed continuing alwayes upon the Tower,
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              the arches of the circumference C I are exactly equal, anſwering
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              under the ſame C F, F G, G H, &c. </s>
              <s>Whence followeth the third
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                <arrow.to.target n="marg332"/>
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              wonder, That the true and real motion of the ſtone is never
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              lerated, but alwayes even and uniforme, ſince that all the equal
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              ches noted in the circumference C D, and their reſpondent ones
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              marked in the circumference C I, are paſt in equal times; ſo that
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              we are left at liberty to ſeek new cauſes of acceleration, or of
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              ther motions, ſeeing that the moveable, as well ſtanding upon the
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              Tower, as deſcending thence, alwayes moveth in the ſame faſhion,
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              that is, circularly, with the ſame velocity, and with the ſame
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              formity. </s>
              <s>Now tell me what you think of this my fantaſtical
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              jecture.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg330"/>
                <emph type="italics"/>
              A moveable
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              ting from the top of
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              the Tower, moveth
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              in the
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              rence of a circle.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg331"/>
                <emph type="italics"/>
              It moveth neither
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              more nor leſſe, than
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              if it had ſtaid
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              wayes there.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg332"/>
                <emph type="italics"/>
              It moveth with
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              an uniform, not
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              an accelerate
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              tion.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>I muſt tell you, that I cannot with words ſufficiently
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              expreſſe how admirable it ſeemeth to me; and for what at
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              ſent offereth it ſelf to my underſtanding, I cannot think that the
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              buſineſs happeneth otherwiſe; and would to God that all the
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              demonſtrations of Philoſophers were but half ſo probable as this.
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              </s>
              <s>However for my perfect ſatisfaction I would gladly hear how you
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              prove thoſe arches to be equal.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>The demonſtration is moſt eaſie. </s>
              <s>Suppoſe to your ſelf
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              a line drawn from I to E. </s>
              <s>And the Semidiameter of the circle CD,
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              that is, the line C A, being double the Semidiameter C E of the </s>
            </p>
          </chap>
        </body>
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    </archimedes>
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