Chapter 20 - Page 2

pierced by the hand ofman. But whether it be the hand of nature or not does not matter.Supper time is come; let us sup."

Hans prepared some food. I scarcely ate, and I swallowed down the fewdrops of water rationed out to me. One flask half full was all we hadleft to slake the thirst of three men.

After their meal my two companions laid themselves down upon theirrugs, and found in sleep a solace for their fatigue. But I could notsleep, and I counted every hour until morning.

On Saturday, at six, we started afresh. In twenty minutes we reacheda vast open space; I then knew that the hand of man had not hollowedout this mine; the vaults would have been shored up, and, as it was,they seemed to be held up by a miracle of equilibrium.

This cavern was about a hundred feet wide and a hundred and fifty inheight. A large mass had been rent asunder by a subterraneandisturbance. Yielding to some vast power from below it had brokenasunder, leaving this great hollow into which human beings were nowpenetrating for the first time.

The whole history of the carboniferous period was written upon thesegloomy walls, and a geologist might with ease trace all its diversephases. The beds of coal were separated by strata of sandstone orcompact clays, and appeared crushed under the weight of overlyingstrata.

At the age of the world which preceded the secondary period, theearth was clothed with immense vegetable forms, the product of thedouble influence of tropical heat and constant moisture; a vapouryatmosphere surrounded the earth, still veiling the direct rays of thesun.

Thence arises the conclusion that the high temperature then existingwas due to some other source than the heat of the sun. Perhaps eventhe orb of day may not have been ready yet to play the splendid parthe now acts. There were no 'climates' as yet, and a torrid heat,equal from pole to equator, was spread over the whole surface of theglobe. Whence this heat? Was it from the interior of the earth?

Notwithstanding the theories of Professor Liedenbrock, a violent heatdid at that time brood within the body of the spheroid. Its actionwas felt to the very last coats of the terrestrial crust; the plants,unacquainted with the beneficent influences of the sun, yieldedneither flowers nor scent. But their roots drew vigorous life fromthe burning soil of the early days of this planet.

There were but few trees. Herbaceous plants alone existed. There weretall grasses, ferns, lycopods, besides sigillaria, asterophyllites,now scarce plants, but then the species might be counted by thousands.

The coal measures owe their origin to this period of profusevegetation. The yet elastic and yielding crust of the earth obeyedthe fluid forces beneath. Thence innumerable fissures anddepressions. The plants, sunk underneath the waters, formed bydegrees into vast accumulated masses.

Then came the chemical action of