Theorem II.
8, 9.
The Repreſentation of a Figure, parallel to
the perſpective Plane, is ſimilar to the ſaid Figure; and
the Sides of the ſaid Figure are to their Repreſen-
tations, as the Diſtance of the Eye from the Plane
of the Figure, to the Diſtance of the Eye from the
perſpective Plane.
the perſpective Plane, is ſimilar to the ſaid Figure; and
the Sides of the ſaid Figure are to their Repreſen-
tations, as the Diſtance of the Eye from the Plane
of the Figure, to the Diſtance of the Eye from the
perſpective Plane.
The given Figure is A B C D.
We are firſt to
11Fig. 4. prove, that its Repreſentation a b c d, is ſimilar
thereto; that is, that the correſponding Angles
of theſe two Figures A B C D, a b c d, are equal,
and their Sides proportional.
11Fig. 4. prove, that its Repreſentation a b c d, is ſimilar
thereto; that is, that the correſponding Angles
of theſe two Figures A B C D, a b c d, are equal,
and their Sides proportional.
I.
The Angles are equal, becauſe the 224.
of which the two Figures conſiſt, are parallel be-
tween themſelves.
tween themſelves.