the nucleus being less and less luminous. By going
back as far as possible, we thus arrive at a nebulosity
so diffused that its existence could hardly be suspected.

"For a long time the peculiar disposition of certain
stars, visible to the unaided eye, has struck philosophical
observers. Mitchell has already remarked
how little probable it is that the stars in the Pleiades,
for example, could have been contracted into the small
space which encloses them by the fortuity of chance
alone, and he has concluded that this group of stars,
and similar groups which the skies present to us, are
the necessary result of the condensation of a nebula,
with several nuclei, and it is evident that a nebula, by
continually contracting, towards these various nuclei,
at length would form a group of stars similar to the
Pleiades. The condensation of a nebula with two
nuclei would form a system of stars close together,
turning one upon the other, such as those double stars
of which we already know the respective movements.

"But how did the solar atmosphere determine the
movements of the rotation and revolution of the planets
and satellites? If these bodies had penetrated very
deeply into this atmosphere, its resistance would have
caused them to fall into the sun. We can therefore
conjecture that the planets were formed at their successive
limits by the condensation of a zone of vapors
which the sun, on cooling, left behind, in the plane of
his equator.