Gravesande, Willem Jacob 's
,
An essay on perspective
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on PERSPECTIVE.
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actly determined, this Method ought not then to
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be uſed.</
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<
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III.</
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">To find the Appearance of the Diviſions of a
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Line in the Geometrical Plane.</
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<
s
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">Let A B be a Line, whoſe Appearance is ab.
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Now to find the Repreſentation of the Diviſions
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of this Line, there muſt be Lines drawn from
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the Diviſions of the Line to the Eye, whoſe
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Interſections with a b will give the Points
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ſought.</
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<
s
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">Note, When theſe Lines very obliquely cut
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a b, the following Way ought to uſed.</
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<
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. II.</
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viſions of the Line G C, make choice of the
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Point D at Pleaſure without this Line, and find
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the Repreſentation d thereof; </
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through the propoſed Diviſions to the Point D;
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</
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<
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tinued out cut the Baſe Line, draw other Lines
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through the Repreſentation d, which will cut c g
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the Repreſentation of C G in the Points ſought.</
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<
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IV.</
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Figure on the Geometrical Plane into Perſpective.</
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<
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">The Repreſentation of any Kinds of Figures
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may be found by any one of the Methods
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Problem I. </
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</
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<
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">and may be firſt uſed in finding the
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ſentations of Points, or ſometimes of one
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only; </
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<
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