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

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    <archimedes>
      <text>
        <body>
          <chap>
            <p type="main">
              <s>
                <pb xlink:href="040/01/369.jpg" pagenum="349"/>
              bed circle ſhall be in the line F G, which let be the point I; and
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              becauſe that of ſuch lines as are drawn from the point G, which
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              is not the centre, unto the circumference of the circumſcribed
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              circle, the biggeſt is that which paſſeth by the centre, G F ſhall
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              be bigger than any other that is drawn from the point G, to the
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              circumference of the ſaid circle; and therefore that
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              rence will cut the line G H (which is equal to the line G F) and
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              cutting G H, it will alſo cut A H. </s>
              <s>Let it cut it in L, and
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              joyn the line L B. </s>
              <s>Theſe two angles, therefore, A F B and A L B
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              ſhall be equal, as being in the ſame portion of the circle
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              cumſcribed. </s>
              <s>But A L B external, is bigger than the internal H;
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              therefore the angle F is bigger than the angle H. </s>
              <s>And by the
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              ſame method we might demonſtrate the angle H to be bigger
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              than the angle E, becauſe that of the circle deſcribed about the
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              triangle A H B, the centre is in the perpendicular G F, to which
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              the line G H is nearer than the line G E, and therefore the
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              cumference of it cutteth G E, and alſo A E, whereupon the
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              poſition is manifeſt. </s>
              <s>We will conclude from hence, that the
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              ference of appearance, (which with the proper term of art, we
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              might call the Parallax of the fixed ſtars) is greater, or leſſe,
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              cording as the Stars obſerved are more or leſſe adjacent to the
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              Pole of the Ecliptick, ſo that, in concluſion of thoſe Stars that
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              are in the Ecliptick it ſelf, the ſaid diverſity is reduced to nothing.
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              </s>
              <s>In the next place, as to the Earths acceſſion by that motion to,
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                <arrow.to.target n="marg664"/>
                <lb/>
              or receſſion from the Stars, it appeareth to, and recedeth from
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              thoſe that are in the Ecliptick, the quantity of the whole
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              ter of the grand Orb, as we did ſee even now, but that acceſſion
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              or receſſion to, or from the ſtars about the Pole of the Ecliptick,
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              is almoſt nothing; and in going to and from others, this
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              rence groweth greater, according as they are neerer to the
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              tick. </s>
              <s>We may, in the third place, know, that the ſaid difference
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                <arrow.to.target n="marg665"/>
                <lb/>
              of Aſpect groweth greater or leſſer, according as the Star
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              ved ſhall be neerer to us, or farther from us. </s>
              <s>For if we draw
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              nother Meridian, leſſe diſtant from the Earth; as for example,
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              this D F I [
                <emph type="italics"/>
              in Fig.
                <emph.end type="italics"/>
              7.] a Star placed in F, and ſeen by the ſame
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              ray A F E, the Earth being in A, would, in caſe it ſhould be
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              ſerved from the Earth in B, appear according to the ray B F, and
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              would make the angle of difference, namely, B F A, bigger
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              than the former A E B, being the exteriour angle of the
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              gle B F E.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg661"/>
                <emph type="italics"/>
              An Indice in
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              the fixed ſtars like
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              to that which is
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              ſeen in the
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              nets, is an
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              ment of the Earths
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              annual motion.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg662"/>
                <emph type="italics"/>
              The fixed ſtars
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              without the
                <lb/>
              tick elevate and
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              deſcend more or
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              leſſe, according to
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              their diſtance from
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              the ſaid Ecliptick.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg663"/>
              *
                <emph type="italics"/>
              i. </s>
              <s>e.
                <emph.end type="italics"/>
              of the
                <lb/>
              cliptick.</s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg664"/>
                <emph type="italics"/>
              The Earth
                <lb/>
              proacheth or
                <lb/>
              deth from the
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              ed ſtars of the
                <lb/>
              cliptick, the
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              tity of the
                <lb/>
              ter of the Grand
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              Orb.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="margin">
              <s>
                <margin.target id="marg665"/>
                <emph type="italics"/>
              The ſtars
                <lb/>
              er to us make
                <lb/>
              greater differences
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              than the more
                <lb/>
              more.
                <emph.end type="italics"/>
              </s>
            </p>
            <p type="main">
              <s>SAGR. </s>
              <s>With great delight, and alſo benefit have I heard
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              your diſcourſe; and that I may be certain, whether I have
                <lb/>
                <arrow.to.target n="marg666"/>
                <lb/>
              ly underſtood the ſame, I ſhall give you the ſumme of the
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              cluſions in a few words. </s>
              <s>As I take it, you have explained to us
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              the different appearances, that by means of the Earths annual </s>
            </p>
          </chap>
        </body>
      </text>
    </archimedes>
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