ctly
spherical, and absolutely smooth; and to cover it with mountains, and
scoop it out into valleys, was an act of impiety which defaced the
regular forms which Nature herself had imprinted. It was in vain that
Galileo appealed to the evidence of observation, and to the actual
surface of our own globe. The very irregularities on the moon were, in
his opinion, the proof of divine wisdom; and had its surface been
absolutely smooth, it would have been "but a vast unblessed desert, void
of animals, of plants, of cities, and of men--the abode of silence and
inaction--senseless, lifeless, soulless, and stripped of all those
ornaments which now render it so varied and so beautiful."

In examining the fixed stars, and comparing them with the planets,
Galileo observed a remarkable difference in the appearance of their
discs. All the planets appeared with round globular discs like the moon;
whereas the fixed stars never exhibited any disc at all, but resembled
lucid points sending forth twinkling rays. Stars of all magnitudes he
found to have the same appearance; those of the fifth and sixth
magnitude having the same character, when seen through a telescope, as
Sirius, the largest of the stars, when seen by the naked eye. Upon
directing his telescope to nebulae and clusters of stars, he was
delighted to find that they consisted of great numbers of stars which
could not be recognised by unassisted vision. He counted no fewer than
_forty_ in the cluster called the _Pleiades_, or _Seven Stars_; and he
has given us drawings of this constellation, as well as of the belt and
sword of Orion, and of the nebula of Praesepe. In the great nebula of the
Milky Way, he descried crowds of minute stars; and he concluded that
this singular portion of the heavens derived its whiteness from still
smaller stars, which his telescope was unable to separate.

Important and interesting as these discoveries were, they were thrown
into the shade by those to which he was led during an accurate
examination of the planets with a more powerful telescope. On the 7th of
January 1610, at one o'clock in the morning, when he directed his
telescope to Jupiter, he observed three stars near the body of the
planet, two being to the east and one to the west of him. They were all
in a straight line, and parallel to the ecliptic, and appeared brighter
than other stars of the same magnitude. Believing them to be fixed
stars, he paid no great attention to their distances