Gravesande, Willem Jacob 's, An essay on perspective

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        <div xml:id="echoid-div102" type="section" level="1" n="57">
          <p>
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              <pb o="28" file="0056" n="61" rhead="An ESSAY"/>
            ſinding the reſt. </s>
            <s xml:id="echoid-s754" xml:space="preserve">But yet the Work may be
              <lb/>
            ſhorten’d by the two precedent Problems, as we
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            ſhall ſhew in the following Examples.</s>
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        <div xml:id="echoid-div104" type="section" level="1" n="58">
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            <emph style="sc">Example</emph>
          I.</head>
          <p style="it">
            <s xml:id="echoid-s756" xml:space="preserve">To throw a Pentagon having one Side parallel to
              <lb/>
            the Baſe Line, into Perſpective.</s>
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          </p>
          <p>
            <s xml:id="echoid-s758" xml:space="preserve">Let A B C D E, be the propoſed Pentagon,
              <lb/>
              <note position="left" xlink:label="note-0056-01" xlink:href="note-0056-01a" xml:space="preserve">Fig. 15.</note>
            wherein draw the Line B D which will be paral-
              <lb/>
            lel to A E, becauſe the Pentagon is a regular
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            one.</s>
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          </p>
          <p>
            <s xml:id="echoid-s760" xml:space="preserve">Now find the Repreſentation of the ſaid
              <note symbol="*" position="left" xlink:label="note-0056-02" xlink:href="note-0056-02a" xml:space="preserve">42.</note>
            Lines A E and B D, and you will have the Re-
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            preſentation of four of the Corners of the Pen-
              <lb/>
            tagon; </s>
            <s xml:id="echoid-s761" xml:space="preserve">and to determine the Repreſentation of
              <lb/>
            the fifth Corner, find the Appearance of
              <note symbol="*" position="left" xlink:label="note-0056-03" xlink:href="note-0056-03a" xml:space="preserve">43.</note>
            Line drawn from C to E, which in this Example
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            is parallel to A B, which is ſuppoſed parallel
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            to the Baſe Line.</s>
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        <div xml:id="echoid-div107" type="section" level="1" n="59">
          <head xml:id="echoid-head61" xml:space="preserve">
            <emph style="sc">Example</emph>
          II.</head>
          <p style="it">
            <s xml:id="echoid-s763" xml:space="preserve">To throw a Parallelogram, divided into ſeveral
              <lb/>
            other Parallelograms into Perſpective.</s>
            <s xml:id="echoid-s764" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s765" xml:space="preserve">Let A B C D be a Parallelogram, divided
              <lb/>
              <note position="left" xlink:label="note-0056-04" xlink:href="note-0056-04a" xml:space="preserve">Fig. 17.</note>
            into ſeveral other Parallelograms.</s>
            <s xml:id="echoid-s766" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s767" xml:space="preserve">Draw the Line O G thro’ the Eye O parallel to
              <lb/>
            the Side A D, cutting the Horizontal Line in G;
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            </s>
            <s xml:id="echoid-s768" xml:space="preserve">likewiſe draw O F parallel to the Side A B cutting
              <lb/>
            the Horizontal Line in F, and produce the Sides
              <lb/>
            of the Parallelogram, and the Lines dividing it,
              <lb/>
            to the Baſe Line; </s>
            <s xml:id="echoid-s769" xml:space="preserve">then from the Points wherein
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            A D and C B, and the Lines parallel thereto
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            cut the Baſe Line, draw Lines to the Point G. </s>
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              <lb/>
            Alſo from the Points wherein A B and C D and
              <lb/>
            their parallels cut the ſaid Line, draw Lines to
              <lb/>
            the Point F, whoſe Interſections with </s>
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