BIELA'S COMET, SPLIT IN TWO 409

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RAGNAROK:

THE AGE OF FIRE AND GRAVEL.

PART I.

The Drift

CHAPTER I.

THE CHARACTERISTICS OF THE DRIFT.

READER,--Let us reason together:--

What do we dwell on? The earth. What part of the earth? The latest
formations, of course. We live upon the top of a mighty series of
stratified rocks, laid down in the water of ancient seas and lakes,
during incalculable ages, said, by geologists, to be from _ten to
twenty miles in thickness_.

Think of that! Rock piled over rock, from the primeval granite
upward, to a height _four times greater than our highest mountains_,
and every rock stratified like the leaves of a book; and every leaf
containing the records of an intensely interesting history,