d not sleep, I lay counting the hours until
morning.

The next morning, Saturday, at six o'clock, we started again. Twenty
minutes later we suddenly came upon a vast excavation. From its mighty
extent I saw at once that the hand of man could have had nothing to do
with this coal mine; the vault above would have fallen in; as it was, it
was only held together by some miracle of nature.

This mighty natural cavern was about a hundred feet wide, by about a
hundred and fifty high. The earth had evidently been cast apart by some
violent subterranean commotion. The mass, giving way to some prodigious
upheaving of nature, had split in two, leaving the vast gap into which
we inhabitants of the earth had penetrated for the first time.

The whole singular history of the coal period was written on those dark
and gloomy walls. A geologist would have been able easily to follow the
different phases of its formation. The seams of coal were separated by
strata of sandstone, a compact clay, which appeared to be crushed down
by the weight from above.

At that period of the world which preceded the secondary epoch, the
earth was covered by a coating of enormous and rich vegetation, due to
the double action of tropical heat and perpetual humidity. A vast
atmospheric cloud of vapor surrounded the earth on all sides, preventing
the rays of the sun from ever reaching it.

Hence the conclusion that these intense heats did not arise from this
new source of caloric.

Perhaps even the star of day was not quite ready for its brilliant
work--to illumine a universe. Climates did not as yet exist, and a level
heat pervaded the whole surface of the globe--the same heat existing at
the North Pole as at the equator.

Whence did it come? From the interior of the earth?

In spite of all the learned theories of Professor Hardwigg, a fierce and
vehement fire certainly burned within the entrails of the great
spheroid. Its action was felt even to the very topmost crust of the
earth; the plants then in existence, being deprived of the vivifying
rays of the sun, had neither buds, nor flowers, nor odor, but their
roots drew a strong and vigorous life from the burning earth of early
days.

There were but few of what may be called trees--only herbaceous plants,
immense turfs, briers, mosses, rare families, which, however, in those
days were counted by tens and tens of thousands.

It is entirely to this exuberant vegetation that coal owes its origin.
T