THIS BOOK OF EARTHS began years ago, with a single little figure
of Earth taken from what old book I do not know. For a long time
it lay by itself; then another, come upon by chance, was laid
beside it; and still others as I happened on them, always by
chance. Old odd maps joined the casual collection--maps of the
Earth, the Moon, the heavens. It was never a collection in the
usual sense of the word, because it was so casual; but, such as
it was, it is the origin of this book. For it occurred to me,
not long ago, that it would be "fun" to put them all together,
and many others with them, chosen to fill in the gaps of the
original group. Luckily for the fun of it, the search about to
begin would not be limited to what we know about the Earth, else
it would have ended before it began; for we live in a universe
of which we know little, and on a planet of which we know
perhaps less. It would include not only what we know, or think
to-day we know, but also any-thing that has been believed or
felt or no more than "