“As for the earth, out of it cometh bread, and under it is turned up as it were fire.”—Job.
Suppose this lump of coal could speak, what would it say? Would it not say something like this: “To get me up out of the earth involves dirt, danger, slush, and much tallow-candle; but now you have me, let me tell you my story, for though black I am comely, and but for me—but I anticipate. Now and then I make a dust in your libraries, and inadvertently shoot out sparks and firestones, but nevertheless I am of more use to man than the old granite or the proudest Parian marble; you may get a long way in philosophy, but you will never get beyond coal. I am the real Koh-i-noor of the British empire; and though I can’t, like my namesake, put on a white dress, I am nevertheless worth the soiling of your whitest gloves. Chemistry makes no discoveries without me: I light the fire of the laboratory, and furnish man with the means of every crucial test. Civilization wants me every day on land and sea, and though in one sense my labours end in smoke, in another they end in commerce, progress, national brotherhood, and interchanging productions of every clime. The poor student needs me, for I light his lamp, warm his feet, and cook his food while he is doing sweat-of-brain work for others. And best of all, the poor man is a rich man when he has me; he knows that next of kin to good food is good fuel, and man by my help is making such progress, that the day will come when every man will sit by his own blazing fire, instead of seeking joy elsewhere amidst false and pernicious excitements.”
Something like this our friend Coal would be sure to say; and that Coal may not complain of any aloofness on our parts, let us proceed to an examination of the carboniferous system.
“’Tis very pregnant,
The jewel that we find, we stoop and take it,
Because we see it; but what we do not see,
We tread upon, and never think of it.”
Measure for Measure.
The carboniferous system is not all coal; underlying, and often overlying, the coal measures, for the most part, is the mountain limestone, a formation pre-eminently rich in marine fossils. During the tremendous convulsions experienced by the earth immediately after the deposition of the old red sandstone, a vast sea of lime, thick, muddy, and hot, seems to have been poured out over a large portion of the British islands and elsewhere. This flow of liquid lime covered and encased many then existing animals, and we now find it full of fossils of the crinoidean family, a few molluscs, and traces of fish. We shall not, however, stay to examine these now, as we shall meet with them again in the Oolite; our attention will be limited to that part of the carboniferous system which includes only the coal measures, properly so called.
Coal is a vegetable that, by chemical change and by mechanical pressure, has become a bituminous mineral; and this will render it needful to say a word or two on the ancient vegetable kingdom. The vast quantities[[56]] of remains of leaves, ferns, and stems of trees, found in the coal measures, are not in themselves evidence sufficient of the vegetable origin of coal; we arrive at that conclusion in consequence of the researches of modern philosophers, who having applied the powers of the microscope to the internal structure of coal, have discovered the cellular and reticular construction of vegetable life beautifully preserved, and thus previous convictions have become certainties. The examination of the ancient vegetable kingdom is, however, attended with much difficulty, in consequence of the total destruction in most cases of the stems and trunks of the plants, and the entire absence, in consequence of pressure, of all fructification on the fronds of the ferns. If we take an existing species of fern, say the rare and delicate “maiden-hair fern,”[[57]] one of the smallest and most elegant ferns of England, we find the fructification very distinct on the under side, and the different methods in which this fructification is arranged is now the principal guide in the classification of ferns. But if we take a fossil fern, say the pecopteris, found in the coal measures, we shall see that there has been so much dislocation and crushing, that all appearance of seed-vessels has disappeared. The following sketch will explain this.