"brilliant flashes of silence."

But I trust we agree thus far that neither water nor ice caused the
Drift. Water and ice were doubtless associated with it, but neither
produced it.

What, now, are the elements of the problem to be solved?

First, we are to find something that instantaneously increased to a
vast extent the heat of our planet, vaporized the seas, and furnished
material for deluges of rain, and great storms of snow, and
accumulations of ice north and south of the equator and in the high
mountains.

Secondly, we are to find something that, _coming from above_,
smashed, pounded, and crushed "as with a maul," and rooted up as with
a plow, the gigantic rocks of the surface, and scattered them for
hundreds of miles from their original location.

{p. 64}

Thirdly, we are to find something which brought to the planet vast,
incalculable masses of clay and gravel, which did not contain any of
the earth's fossils; which, like the witches of Macbeth,

Look not like th' inhabitants of earth,
And yet are on it; "

which are marked after a fashion which can not be found anywhere else
on earth; produced in a laboratory which has not yet been discovered