to spread through its pores. This caused a peculiar form of vegetation,
such as is probably produced on the surface of the inferior planets,
Venus or Mercury, which revolve nearer than our earth around
the radiant sun of our system.

The soil of the continents was covered with immense forests.
Carbonic acid, so suitable for the development of the vegetable
kingdom, abounded. The feet of these trees were drowned in a sort
of immense lagoon, kept continually full by currents of fresh
and salt waters. They eagerly assimilated to themselves the carbon
which they, little by little, extracted from the atmosphere,
as yet unfit for the function of life, and it may be said
that they were destined to store it, in the form of coal,
in the very bowels of the earth.

It was the earthquake period, caused by internal convulsions,
which suddenly modified the unsettled features of the
terrestrial surface. Here, an intumescence which was to become
a mountain, there, an abyss which was to be filled with an ocean
or a sea. There, whole forests sunk through the earth's crust,
below the unfixed strata, either until they found a resting-place,
such as the primitive bed of granitic rock, or, settling together
in a heap, they formed a solid mass.

As the waters were contained in no bed, and were spread over every
part of the globe, they rushed where they liked, tearing from
the scarcely-formed rocks material with which to compose schists,
sandstones, and limestones. This the roving waves bore over
the submerged and now peaty forests, and deposited above them
the elements of rocks which were to superpose the coal strata.