The atmosphere absorbs some portion of the light which it receives. It
is not all reflected or refracted or even penetrative.

Objects seen under various degrees of light, either convected or
retarded by different media, appear near or distant, distinct or
confused. Thus, we are often surprised at the apparent nearness and
brightness of an opposite shore or neighboring island, in some
conditions of the air, while at other times they seem distant and lie
in shadowy obscurity.

The looming up of a vessel on the water is another common instance of
the principle of refraction.

It has been noticed by almost every one, that, during the warm and
moist nights of summer, the moon, as she rises above the horizon,
appears much larger than when at the zenith. So the setting sun is
seen of apparently increased size. Sir John Herschel asserts that the
appearance is an illusion, and so do some others. Professor Carey
says, that, if we look through a paper tube at the moon when on the
horizon, the paper being folded so as to make the aperture of its
exact size, and then look again at it when it reaches the zenith, we
shall find there is no difference.

On the other hand, an experiment is offered by a German Professor, of
the name of Milo, of this kind: If we look through a tube so
constructed as to have one side filled with spirits of wine and the
other with common air, the half of the object seen through the former
will be found to appear much larger to the eye than the other half
seen through the latter.