The artists repository and drawing magazine: exhibiting the principles of the polite arts in their various branches (3.1789)

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diminution of objects is caused by the smali--
nefs of the angle under which they are been,
and this is one reason why at a distance they
become to us invisible, or may be said to va-
nish. But another cause is the various quality
and force of the rays emitted from object*
in various situations.
It is evident, that an object which is near,
and consequently occupies a greater propor-
tion of the rays received by the pupil, will
posiess a larger space on the retina, and having
less distance to shoot its rays (as it wrere),
they enter the eye in sull force ; whereas the
removal of this objeft to a further station, not
only diminishes the quantity of its rays, but also
their lustre and vivacity ; they become seeble
and dim. This essect is natural to its situation,
but if, beside this effect natural to its situa-
tion, we advert to the superior advantages pos-
sessed by objefts still remaining near the eye,
we find not only that they occupy the place of
the former; but by the vivacity and strength
of the images they raise, they out-shine, so to
term it, their diltant friend; unless, indeed,
as in the obscurity of night, the nearer ob-
jects are void of illumination, while the remote
are strongly enlightened.
I proceed now from natural causes, to no-
tice