philosopher, Democritus, that the faintly white zone which spans the
sky under the name of the Milky Way, might be only a dense collection
of stars too remote to be distinguished. This conjecture has been
verified by the instruments of modern astronomers, and some
speculations of a most remarkable kind have been formed in connexion
with it. By the joint labours of the two Herschels, the sky has been
"gauged" in all directions by the telescope, so as to ascertain the
conditions of different parts with respect to the frequency of the
stars. The result has been a conviction that, as the planets are
parts of solar systems, so are solar systems parts of what may be
called astral systems--that is, systems composed of a multitude of
stars, bearing a certain relation to each other. The astral system
to which we belong, is conceived to be of an oblong, flattish form,
with a space wholly or comparatively vacant in the centre, while the
extremity in one direction parts into two. The stars are most
thickly sown in the outer parts of this vast ring, and these
constitute the Milky Way. Our sun is believed to be placed in the
southern portion of the ring, near its inner edge, so that we are
presented with many more stars, and see the Milky Way much more
clearly, in that direction, than towards the north, in which line our
eye has to traverse the vacant central space. Nor is this all. Sir
William Herschel, so early as 1783, detected a motion in our solar
system with respect to the stars, and announced that it was tending
towards the star ?, in the constellation Hercules. This has been
generally verified by recent and more exact calculations, {5} which
fix on a point in Hercules, near the star 143 of the 17th hour,
according to Piozzi's catalogue, as that towards which our sun is
proceeding. It is, therefore, receding from the inner edge of the
ring. Motions of this kind, through such vast regions of space, must
be long in producing any change sensible to the inhabitants of our