asks how they, including our own world, came into being.

We now approach this subject with a clearer perception of the
work we have to do. The universe is a vast expanse of ether, and
somehow or other this ether gives rise to atoms of matter. We may
imagine it as a spacious chamber filled with cosmic dust;
recollecting that the chamber has no walls, and that the dust
arises in the ether itself. The problem we now approach is, in a
word: How are these enormous stretches of cosmic dust, which we
call matter, swept together and compressed into suns and planets?
The most famous answer to this question is the "nebular
hypothesis." Let us see, briefly, how it came into modern
science.

We saw that some of the ancient Greek speculators imagined their
infinite number of atoms as scattered originally, like dust,
throughout space and gradually coming together, as dust does, to
form worlds. The way in which they brought their atoms together
was wrong, but the genius of Democritus had provided the germ of
another sound theory to the students of a more enlightened age.
Descartes (1596-1650) recalled the idea, and set out a theory of
the evolution of stars and planets from a diffused chaos of
particles. He even ventured to say that the earth was at one time
a small white-hot sun, and that a solid crust had gradually
formed round its molten core. Descartes had taken refuge in
Sweden from his persecutors, and it is therefore not surprising
that that strange genius Swedenborg shortly afterwards developed
the same idea. In the middle of the eighteenth century the great
French naturalist, Buffon, followed and improved upon Descartes
and Swedenborg. From Buffon's work it was learned by the German