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

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      <text>
        <body>
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            <p type="main">
              <s>
                <pb xlink:href="040/01/190.jpg" pagenum="172"/>
                <arrow.to.target n="marg365"/>
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              them. </s>
              <s>From the things premiſed I gather that the project ſwiftly
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              ſwinged round by the projicient, in its ſeparating from it, doth
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              tain an
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              impetus
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              of continuing its motion by the right line, which
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              toucheth the circle deſcribed by the motion of the projicient in
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              the point of ſeparation, by which motion the project goeth
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              tinually receding from the centre of the circle deſcribed by the
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              motion of the projicient.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg365"/>
                <emph type="italics"/>
              The project
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              veth by the
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              gent of the circle of
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              the motion
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              dent in the point of
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              ſeparation.
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              </s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>You know then by this time the reaſon why grave
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              dies ſticking to the rim of a wheele, ſwiftly moved, are extruded
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              and thrown beyond the circumference to yet a farther diſtance
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              from the centre.</s>
            </p>
            <p type="main">
              <s>SIMP. </s>
              <s>I think I underſtand this very well; but this new
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              ledg rather increaſeth than leſſeneth my incredulity that the Earth
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              can turn round with ſo great velocity, without extruding up into
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              the sky, ſtones, animals,
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              &c.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SALV. </s>
              <s>In the ſame manner that you have underſtood all this,
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              you ſhall, nay you do underſtand the reſt: and with recollecting
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              your ſelf, you may remember the ſame without the help of
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              thers: but that we may loſe no time, I will help your memory
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              therein. </s>
              <s>You do already know of your ſelf, that the circular
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              tion of the projicient impreſſeth on the project an
                <emph type="italics"/>
              impetus
                <emph.end type="italics"/>
              of
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              ving (when they come to ſeparate) by the right Tangent, the
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              circle of the motion in the point of ſeparation, and continuing
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              long by the ſame the motion ever goeth receding farther and
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              ther from the projicient: and you have ſaid, that the project
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              would continue to move along by that right line, if there were not
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              by its proper weight an inclination of deſcent added unto it; from
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              which the incurvation of the line of motion is derived. </s>
              <s>It ſeems
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              moreover that you knew of your ſelf, that this incurvation
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              ways bended towards the centre of the Earth, for thither do all
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              grave bodies tend. </s>
              <s>Now I proceed a little farther, and ask you,
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              ther the moveable after its ſeparation, in continuing the right
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              tion goeth always equally receding from the centre, or if you will,
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              from the circumference of that circle, of which the precedent
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              tion was a part; which is as much as to ſay, Whether a moveable,
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              that forſaking the point of a Tangent, and moving along by the
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              ſaid Tangent, doth equally recede from the point of contact, and
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              from the circumference of the circle?</s>
            </p>
            <p type="main">
              <s>SIMP. No, Sir: for the Tangent near to the point of contact,
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              recedeth very little from the circumference, wherewith it keepeth
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              a very narrow angle, but in its going farther and farther
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              off, the diſtance always encreaſeth with a greater proportion; ſo
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              that in a circle that ſhould have
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              v. </s>
              <s>g.
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              ten yards of diameter, a point
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              of the Tangent that was diſtant from the contact but two palms,
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              would be three or four times as far diſtant from the circumference </s>
            </p>
          </chap>
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