Gravesande, Willem Jacob 's, An essay on perspective

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        <div xml:id="echoid-div107" type="section" level="1" n="59">
          <p>
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              <pb o="29" file="0057" n="62" rhead="on PERSPECTIVE."/>
            drawn to the Point G, will give the Appearance
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            ſought.</s>
            <s xml:id="echoid-s771" xml:space="preserve"/>
          </p>
        </div>
        <div xml:id="echoid-div109" type="section" level="1" n="60">
          <head xml:id="echoid-head62" xml:space="preserve">
            <emph style="sc">Remarks</emph>
          .</head>
          <p>
            <s xml:id="echoid-s772" xml:space="preserve">When this Method cannot be us’d, the Per-
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            ſpective of the Diviſions dividing the Sides of
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            the Parallelogram, mufl be found . </s>
            <s xml:id="echoid-s773" xml:space="preserve">And we
              <note symbol="*" position="right" xlink:label="note-0057-01" xlink:href="note-0057-01a" xml:space="preserve">44.</note>
            often oblig’d to have recourſe to this Expedient,
              <lb/>
            notwithſtanding the accidental Points, G and F,
              <lb/>
            being had. </s>
            <s xml:id="echoid-s774" xml:space="preserve">And this happens, when the Paralle-
              <lb/>
            logram is ſo far diſtant from the perſpective
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            Plane, that its Sides being produc’d, cannot meet
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            the Baſe Line.</s>
            <s xml:id="echoid-s775" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s776" xml:space="preserve">47. </s>
            <s xml:id="echoid-s777" xml:space="preserve">Note, moreover, that this one Example
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            is ſufficient to ſhew how to throw any Kinds of
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            Figures in the Geometrical Plane into Perſpe-
              <lb/>
            ctive. </s>
            <s xml:id="echoid-s778" xml:space="preserve">To effect which, we circumſcribe any
              <lb/>
            Parallelogram about the Figures, which we di-
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            vide into ſeveral others: </s>
            <s xml:id="echoid-s779" xml:space="preserve">Then we throw this
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            Parallelogram (thus divided) into Perſpective,
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            and transfer the given Figure therein, ſo that it
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            may have the ſame Situation with reſpect to
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            the little Parallelograms in the perſpective Plane,
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            as it had in regard to the ſmall Parallelograms
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            in the Geometrical Plane.</s>
            <s xml:id="echoid-s780" xml:space="preserve"/>
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        <div xml:id="echoid-div111" type="section" level="1" n="61">
          <head xml:id="echoid-head63" xml:space="preserve">
            <emph style="sc">Example</emph>
          III.</head>
          <head xml:id="echoid-head64" style="it" xml:space="preserve">48. To throw a circle into Perſpective.</head>
          <p>
            <s xml:id="echoid-s781" xml:space="preserve">The Repreſentation of ſeveral Points of a
              <lb/>
              <note position="right" xlink:label="note-0057-02" xlink:href="note-0057-02a" xml:space="preserve">Fig. 16.</note>
            Circle, or any other Curve Line requir’d to be
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            thrown into perſpective, muſt be found,
              <note symbol="*" position="right" xlink:label="note-0057-03" xlink:href="note-0057-03a" xml:space="preserve">21.</note>
            may be well enough done, by drawing ſeveral
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            Chords in the Circle, or Curve, parallel between
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            themſelves, the Repreſentations of which muſt
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            be found ; </s>
            <s xml:id="echoid-s782" xml:space="preserve">then the Extremities of thoſe
              <note symbol="*" position="right" xlink:label="note-0057-04" xlink:href="note-0057-04a" xml:space="preserve">43.</note>
            </s>
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