3615on PERSPECTIVE.
to the Eye.
Now, as in the latter Situation,
Repreſentatious are drawn upon the Face of the
Perſpective Plane next to the Object, the Per-
ſpective Plane lying down upon its other Face;
what ought to be on the Right Hand, appears on
the Left; and that on the Left, appears on the
Right; producing exactly the ſame Effect, as
looking thro’ the Back-ſide of a Paper, at a Pi-
cture drawn thereon.
Repreſentatious are drawn upon the Face of the
Perſpective Plane next to the Object, the Per-
ſpective Plane lying down upon its other Face;
what ought to be on the Right Hand, appears on
the Left; and that on the Left, appears on the
Right; producing exactly the ſame Effect, as
looking thro’ the Back-ſide of a Paper, at a Pi-
cture drawn thereon.
Yet, notwithſtanding this Deficiency, we pre-
fer the latter way of the Perſpective Plane’s ly-
ing down to the former, for the following Rea-
ſons.
fer the latter way of the Perſpective Plane’s ly-
ing down to the former, for the following Rea-
ſons.
1.
When the Perſpective Plane lies down in
the former manner, it lies upon the Part of the
Geometrical Plane wherein Figures have been
drawn; which, together with the new Lines that
muſt be drawn, cauſes a very great Confuſion,
and always obliges one to copy his Work. An
Inconveniency which the latter Method is ſel-
dom ſubject to.
the former manner, it lies upon the Part of the
Geometrical Plane wherein Figures have been
drawn; which, together with the new Lines that
muſt be drawn, cauſes a very great Confuſion,
and always obliges one to copy his Work. An
Inconveniency which the latter Method is ſel-
dom ſubject to.
2.
We work with much more Eaſe in the
manner I have choſen.
manner I have choſen.
Finally, The Default we have obſerv’d, may
ſeveral ways be remedied. For, in drawing up-
on the Geometrical Plane, we need but place
that on the Right Hand which we have a mind
ſhould appear on the Left; or if the Geometri-
cal Plane be drawn upon Paper, it may be oil’d,
or dipp’d in Varniſh, which will render it tran-
ſparent; and then the Back-ſide of the Paper
may be thrown into Perſpective.
ſeveral ways be remedied. For, in drawing up-
on the Geometrical Plane, we need but place
that on the Right Hand which we have a mind
ſhould appear on the Left; or if the Geometri-
cal Plane be drawn upon Paper, it may be oil’d,
or dipp’d in Varniſh, which will render it tran-
ſparent; and then the Back-ſide of the Paper
may be thrown into Perſpective.
If all this be not found convenient, the ſaid
Default may be eaſily corrected geometrically,
in copying the Work after the Drawings are fi-
niſhed. And this may be yet eaſier done, if
the Figures are expoſed before a Looking-glaſs;
Default may be eaſily corrected geometrically,
in copying the Work after the Drawings are fi-
niſhed. And this may be yet eaſier done, if
the Figures are expoſed before a Looking-glaſs;
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