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.Avast 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.The crust of the vast globe still yielded under the influence of the seething,boiling mass,which was forever at work beneath.Hence arose numerous fissures,and continual falling in of the upper earth.The dense mass of plants being beneath the waters,soon formed themselves into vast agglomerations.
Then came about the action of natural chemistry;in the depths of the ocean the vegetable mass at first became turf,then,thanks to the influence of gases and subterranean fermentation,they underwent the complete process of mineralization.
In this manner,in early days,were formed those vast and prodigious layers of coal,which an ever-increasing consumption must utterly use up in about three centuries more,if people do not find some more economic light than gas,and some cheaper motive power than steam.
All these reflections,the memories of my school studies,came to my mind while I gazed upon these mighty accumulations of coal,whose riches,however,are scarcely likely to be ever utilized.The working of these mines could only be carried out at an expense that would never yield a profit.
The matter,however,is scarcely worthy consideration,when coal is scattered over the whole surface of the globe,within a few yards of the upper crust.As I looked at these untouched strata,therefore,I knew they would remain as long as the world lasts.
While we still continued our journey,I alone forgot the length of the road,by giving myself up wholly to these geological considerations.The temperature continued to be very much the same as while we were traveling amid the lava and the schists.On the other hand my sense of smell was much affected by a very powerful odor.Iimmediately knew that the gallery was filled to overflowing with that dangerous gas the miners call fire damp,the explosion of which has caused such fearful and terrible accidents,making a hundred widows and hundreds of orphans in a single hour.
Happily,we were able to illumine our progress by means of the Ruhmkorff apparatus.If we had been so rash and imprudent as to explore this gallery,torch in hand,a terrible explosion would have put an end to our travels,simply because no travelers would be left.
Our excursion through this wondrous coal mine in the very bowels of the earth lasted until evening.My uncle was scarcely able to conceal his impatience and dissatisfaction at the road continuing still to advance in a horizontal direction.
The darkness,dense and opaque a few yards in advance and in the rear,rendered it impossible to make out what was the length of the gallery.For myself,I began to believe that it was simply interminable,and would go on in the same manner for months.
Suddenly,at six o'clock,we stood in front of a wall.To the right,to the left above,below,nowhere was there any passage.We had reached a spot where the rocks said in unmistakable accents-No Thoroughfare.
I stood stupefied.The guide simply folded his arms.My uncle was silent.
"Well,well,so much the better,"cried my uncle,at last,"I now know what we are about.We are decidedly not upon the road followed by Saknussemm.All we have to do is to go back.Let us take one night's good rest,and before three days are over,I promise you we shall have regained the point where the galleries divided.""Yes,we may,if our strength lasts as long,"I cried,in a lamentable voice.
"And why not?"
"Tomorrow,among us three,there will not be a drop of water.It is just gone.""And your courage with it,"said my uncle,speaking in a severe tone.
What could I say?I turned round on my side,and from sheer exhaustion fell into a heavy sleep disturbed by dreams of water!And Iawoke unrefreshed.
I would have bartered a diamond mine for a glass of pure spring water!