the most accurate counts of stars that have been made fail to show
any difference in their general arrangement in the two hemispheres.
They are just as thick around the south galactic poles as around the
north one. They show the same tendency to crowd towards the Milky Way
in the hemisphere invisible to us as in the hemisphere which we see.
Slight differences and irregularities, are, indeed, found in the
enumeration, but they are no greater than must necessarily arise from
the difficulty of stopping our count at a perfectly fixed magnitude.
The aim of star-counts is not to estimate the total number of stars,
for this is beyond our power, but the number visible with a given
telescope. In such work different observers have explored different
parts of the sky, and in a count of the same region by two observers we
shall find that, although they attempt to stop at the same magnitude,
each will include a great number of stars which the other omits. There
is, therefore, room for considerable difference in the numbers of stars
recorded, without there being any actual inequality between the two
hemispheres.

A corresponding similarity is found in the physical constitution of the
stars as brought out by the spectroscope. The Milky Way is extremely
rich in bluish stars, which make up a considerable majority of the
cloudlike masses there seen. But when we recede from the galaxy on one
side, we find the blue stars becoming thinner, while those having a
yellow tinge become relatively more numerous. This difference of color
also is the same on the two sides of the galactic plane. Nor can any
systematic difference be detected between the proper motions of the
stars in these two hemispheres. If the largest known proper motion is
found in the one, the second largest is in the other. Counting all the
known stars that have proper motions exceeding a given limit, we find
about as many in one hemisphere as in the other. In this respect, also,
the universe appears to be alike through its whole extent. It is the
uniformity thus prevailing through the visible universe, as far as we
can see, in two opposite directions, which inspires us with confidence
in the possibility of ultimately reaching some well-founded conclusion
as to the extent and structure of the system.

All these facts concur in supporting the view of Wright, Kant, and
Herschel as to the form of the universe. The farther out the stars
extend in any direction, the more stars we m