why the orbits of more than a hundred comets already
observed are so elliptical. This hypothesis is therefore
very far from satisfying the preceding phenomena.
Let us see if it is possible to trace them back to their
true cause.

"Whatever may be its ultimate nature, seeing that it
has caused or modified the movements of the planets,
it is necessary that this cause should embrace every
body, and, in view of the enormous distances which
separate them, it could only have been a fluid of immense
extent. In order to have given them an almost
circular movement in the same direction around the
sun, it is necessary that this fluid should have enveloped
the sun as in an atmosphere. The consideration
of the planetary movements leads us then to think
that, on account of excessive heat, the atmosphere of
the sun originally extended beyond the orbits of all
the planets, and that it was successively contracted to
its present limits.

"In the primitive condition in which we suppose the
sun to have been, it resembled a nebula such as the
telescope shows is composed of a nucleus more or less
brilliant, surrounded by a nebulosity which, on condensing
itself towards the centre, forms a star. If it is
conceived by analogy that all the stars were formed in
this manner, it is possible to imagine their previous
condition of nebulosity, itself preceded by other states
in which the nebulous matter was still more diffused,