way in which the moon rules the tides would, I am
sure, interest every thoughtful reader; but there is not room for it
here.

Let us now turn to consider the moon; not as the light which makes our
nights beautiful, nor as the body which governs the mighty ocean in its
tidal sway, but as another world,--the companion planet of the earth.

It has always been a matter not only of the deepest curiosity, but of
the greatest scientific import, whether other planets, and particularly
our own satellite, are inhabited or exhibit any traces whatever of
animal or vegetable life.

One or two astronomers have claimed the discovery of vegetation on the
moon's surface by reason of the periodic appearance of a greenish tint;
but as the power of the telescope can bring the moon to within only
about a hundred and twenty miles of us, these alleged appearances cannot
be satisfactorily verified.

The moon is a globe, two thousand one hundred and sixty-five miles in
diameter; very much less, therefore, than our earth, which has a
diameter of about seven thousand nine hundred and twenty miles.

Thus the moon's surface is less than one thirteenth of the earth's.
Instead of two hundred millions of square miles as the earth has, the
moon has only about fourteen millions of square miles, or about the same
surface as North and South America together, without the great American
Islands of the Arctic regions.

The volume of the earth exceeds that of the moon more than forty-nine
times. But the moon's substance is somewhat lighter. Thus the mass, or
quantity of matter in the moon, instead of being a forty-ninth part of
the earth's, is about an eighty-first part.

This small companion world travels like our own earth around the sun, at
a distance of ninety-three millions of miles. The path of the moon
around the sun is, in fact, so nearly the same as that of the earth that
it would be almost impossible to distinguish one from the other, if they
were both drawn on a sheet of paper a foot or so in diameter.

You may perhaps be surprised to find me thus saying that the moon
travels round the sun, when you have been accustomed to hear that the
moon travels round the earth. In reality, however, it is round the sun
the moon travels, though certainly the moon and the earth circle around
each other.

The distance of the moon from the earth is not always the same; but the
average, or mean distance, amounts to about two hundred and thirty-eight
thou