Sheraton, Thomas; Bensley, Thomas; Mathews, James; Bensley, Thomas [Bearb.]; Mathews, James [Bearb.]; Terry, George [Bearb.]; Jordan, Jeremiah Samuel [Bearb.]; Wayland, L. [Bearb.]: The Cabinet-Maker And Upholsterer's Drawing-Book: In Three Parts (London: Printed For The Author, By T. Bensley; And Sold By J. Mathews ... C. Terry ... J.S. Jordan ... L. Wayland ... And By The Author, 1793)

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From what has been faid on this fubjedt, it is evident that
a perfect picture of objects, as they appear to the human eye.,
cannot be delineated on a plane. It may be done on the
furface of a fphere, when the eye of the fpedfator is fup-
pofed to be in its center; for then every part of the pic-
ture would be equidiffant from the eye, and every ray of
light perpendicular to its own furface, as are the rays y P,
ii, P, &c. of the fphere KL. None of the rays, in this cafe,
could cut the picture obliquely, and confequently no diflor-
tion would appear. But though this be the cafe, yet it will
not afford any folid objection to the certainty of perfpeftive
rules adjufted to a plane; for, by the help of light and ilia-
dow applied in different degrees of ffrength to objects as
they are more or Jefs remote from the eye, and by a judi-
cious choice of the diftance, a picture may be drawn on an
even furface, fo as to deceive the eye, and produce in the
mind fimilar effects with the original or real objects,