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

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            <p type="main">
              <s>
                <pb xlink:href="040/01/168.jpg" pagenum="150"/>
              part but with two onely: but if the ſame bow be uſed, it always
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              receiveth thence three degrees.</s>
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              <s>SIMP. </s>
              <s>It doth ſo; and for this reaſon, ſhooting with the
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              ſame bow in the chariots courſe, the ſhoots cannot be equal.</s>
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            <p type="main">
              <s>SALV. </s>
              <s>I had forgot to ask, with what velocity it is ſuppoſed in
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              this particular experiment, that the chariot runneth.</s>
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            <p type="main">
              <s>SIMP. </s>
              <s>The velocity of the chariot muſt be ſuppoſed to be one
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              degree in compariſon to that of the bow, which is three,</s>
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              <s>SALV. </s>
              <s>Very right, for ſo computation gives it. </s>
              <s>But tell me,
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              when the chariot moveth, doth not all things in the ſame move
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              with the ſame velocity?</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>Yes doubtleſs.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>Then ſo doth the ſhaft alſo, and the bow, and the ſtring,
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              upon which the ſhaft is nock't.</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>They do ſo.</s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>Why then, in diſcharging the ſhaft towards the courſe
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              of the chariot, the bow impreſſeth its three degrees of velocity on
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              a ſhaft that had one degree of velocity before, by means of the
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              chariot which tranſported it ſo faſt towards that part; ſo that in
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              its going off it hath four degrees of velocity. </s>
              <s>On the contrary,
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              in the other ſhoot, the ſame bow conferreth its ſame three degrees
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              of velocity on a ſhaft that moveth the contrary way, with one
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              gree; ſo that in its departing from the bow-ſtring, it hath no more
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              left but onely two degrees of velocity. </s>
              <s>But you your ſelf have
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              already ſaid, that the way to make the ſhoots equal, is to cauſe
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              that the ſhaft be let flie the firſt time with four degrees of velocity,
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              and the ſecond time with two. </s>
              <s>Therefore without changing the
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              bow, the very courſe of the chariot is that which adjuſteth the
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                <arrow.to.target n="marg338"/>
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              flights, and the experiment doth ſo repreſent them to any one who
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              is not either wilfully or naturally incapable of reaſon. </s>
              <s>Now
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              apply this diſcourſe to Gunnery, and you ſhall find, that whether the
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              Earth move or ſtand ſtill, the ſhots made with the ſame force, will
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              always curry equal ranges, to what part ſoever aimed. </s>
              <s>The error
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              of
                <emph type="italics"/>
              Ariſtotle, Ptolomey, Iycho,
                <emph.end type="italics"/>
              your ſelf, and all the reſt, is
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              ed upon that fixed and ſtrong perſuaſion, that the Earth ſtandeth
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              ſtill, which you have not judgment nor power to depoſe, no not
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              when you have a deſire to argue of that which would enſue,
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              ſuppoſing the Earth to move. </s>
              <s>And thus, in the other argument,
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              not conſidering that whil'ſt the ſtone is upon the Tower, it doth,
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              as to moving or not moving, the ſame that the Terreſtrial Globe
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              doth, becauſe you have concluded with your ſelf, that the Earth
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              ſtands ſtill, you always diſcourſe touching the fall of the ſtone, as
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              if it were to depart from reſt: whereas it behooveth to ſay, that
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              if the Earth ſtandeth ſtill, the ſtone departeth from reſt, and
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              ſcendeth perpendicularly; but if the Earth do move, the ſtone </s>
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          </chap>
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