{p. 62}

atmosphere was necessary to lift this gigantic layer of ocean-water out of its bed and into the clouds!

The ice, then, was not the cause of the cataclysm; it was simply one of the secondary consequences.

We must look, then, behind the ice-age for some cause that would prodigiously increase the heat of our atmosphere, and, when we have found that, we shall have discovered the cause of the drift-deposits as well as of the ice.

The solution of the whole stupendous problem is, therefore, heat, not cold.

{p. 63}

PART II.
The Comet.

CHAPTER I.

A COMET CAUSED THE DRIFT.

Now, good reader, we have reasoned together up to this point. To be sure, I have done most of the talking, while you have indulged in what the Rev. Sydney Smith called, speaking of Lord Macaulay, "brilliant flashes of silence."