DOI Page / Citation link:
https://doi.org/10.11588/diglit.62828#0442
tances. For, as in linear perfpedlive, objects are viewed under
a fmaller angle in proportion as they are at a diftance, fo in the
aerial part every tint and fhadow gradually weakens as the object
is fituated at a diftance from the front of the pidlure. The
reafon of this is obvious, when it is admitted that we are made
to fee objects by innumerable beams of light iffuing from them
to the eye. It is eafy then to conceive, that when thefe beams
or rays of light have to make their way through the air from
diflant parts of the horizon to the eye, they mull greatly weaken
before their arrival to it, and therefore fuch diflant objects muft
appear lefs diftindl and more dim in proportion to that diftance.
Hence, in a picture, as in the view given in Plate XXVI. objedls
on the fore ground are not only larger, but they are more made
out, more diftindl, and ftrongly marked. Their lights are
brighter, anxl their fhades are darker, than thofe on the back
ground. This will, perhaps, be more eafily underflood by the
following obfervations on the view.
The tree on the left is neareft to the eye of the fpeciator,.
and is therefore moil made out; its leaves are feen in clufters,
and its fliade is ftrong.
The firft tree on the right, being further back, is lefs dif-
tindl in its parts, and rather fainter in its fliadows; and fo of the
reft in proportion to their diftance.
With
a fmaller angle in proportion as they are at a diftance, fo in the
aerial part every tint and fhadow gradually weakens as the object
is fituated at a diftance from the front of the pidlure. The
reafon of this is obvious, when it is admitted that we are made
to fee objects by innumerable beams of light iffuing from them
to the eye. It is eafy then to conceive, that when thefe beams
or rays of light have to make their way through the air from
diflant parts of the horizon to the eye, they mull greatly weaken
before their arrival to it, and therefore fuch diflant objects muft
appear lefs diftindl and more dim in proportion to that diftance.
Hence, in a picture, as in the view given in Plate XXVI. objedls
on the fore ground are not only larger, but they are more made
out, more diftindl, and ftrongly marked. Their lights are
brighter, anxl their fhades are darker, than thofe on the back
ground. This will, perhaps, be more eafily underflood by the
following obfervations on the view.
The tree on the left is neareft to the eye of the fpeciator,.
and is therefore moil made out; its leaves are feen in clufters,
and its fliade is ftrong.
The firft tree on the right, being further back, is lefs dif-
tindl in its parts, and rather fainter in its fliadows; and fo of the
reft in proportion to their diftance.
With