CHAPTER VI.THE CARBONIFEROUS SYSTEM.

“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 amnevertheless worth the soiling of your whitest gloves.Chemistrymakes no discoveries without me: I light the fire of the laboratory, and furnish man with the means of every crucial test.Civilizationwants 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. Thepoor studentneeds 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, thepoor manis 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.

“’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, bychemical changeand bymechanical 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 ofleaves, 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 somuch dislocation and crushing, that all appearance of seed-vessels has disappeared. The following sketch will explain this.

EXTINCT FERN, AND MAIDEN-HAIR FERN.

“Nothing,” says Professor Ansted, “however, is more certain than that all coal was once vegetable; for in most cases the woody structure may be detected under the microscope, and this, if not in the coal in its ordinary state, at least in the burnt ashes which remain after it has been exposed to the action of heat, and has lost its bituminous and semi-crystalline character. This has been too well and too frequently proved by actual experiment torequire more than the mere statement of the fact.” And here let us say a few words, which to a few perhaps may have the charm of novelty, about the economic history of coal; for as Cowper says that the first curse, “labour,” has, by God’s blessing on it, been “softened into mercy,” so do we add also, in his words, heartily subscribing to their truth,—

“Thus studied, used, and consecrated thus,On earth what is, seems formed indeed for us;Not as the plaything of a froward child,Fretful unless diverted and beguiled;But as scale, by which the soul ascendsFrom mighty means to more important ends;Securely, though by steps but rarely trod,Mounts from inferior beings up to God;And sees, by no fallacious light or dim,Earth made for man, and man himself for Him.”

“Thus studied, used, and consecrated thus,

On earth what is, seems formed indeed for us;

Not as the plaything of a froward child,

Fretful unless diverted and beguiled;

But as scale, by which the soul ascends

From mighty means to more important ends;

Securely, though by steps but rarely trod,

Mounts from inferior beings up to God;

And sees, by no fallacious light or dim,

Earth made for man, and man himself for Him.”

How long coal has been known and used, we cannot certainly tell, but a writer in Lardner’s Cabinet Cyclopædia states that the first mention of coal is in the pages of one Theophrastus, who was, it seems, a pupil of Aristotle. He says, “Those fossil substances that are called coals,” (Greek,ἄνθραξ) “and are broken for use, are earthy; they kindle, however, and burn like wood coals; they are found in Liguria and in the way to Olympias over the mountains,and are used by the smiths.” Cæsar, although he speaks of the metals of the British isles, does not once mention its coal; but it seems more than likely that it was both known and used by the Romans during their occupation of Britain. Horsley, in his “Britannia Romana,” says of Benwell, a village near Newcastle-on-Tyne, “There was a coalry not far from this place, which is judged by those who are best skilled in such affairs to have been wrought by the Romans; and, in digging up the foundations of one of the Roman walled cities, coal cinders very large were dug up, which glowed in the fire like other coal cinders, and were not to be known from them when taken up.”

During the time of the Saxons, we find ourselves on less doubtful ground. In a grant made to the monks of Peterborough Abbey for one night’s annual entertainment, those good old souls had, we find, “ten vessels of Welsh ale, two vessels of common ale, sixty cartloads of wood, and twelve cartloads offossil coal,” (carbonum fossilium.)

The Danes had so much fighting on hand, that they troubled themselves neither with coal nor civilization; and we know little of ourEnglish diamond until we come to Henry the Third’s reign, when, in 1239, a charter was granted to the inhabitants of Newcastle-on-Tyne to dig coals, and we find the coal called for the first time “carbo maris,” or sea-coal, a term retained through all the succeeding centuries. About this time chimneys came into fashion. As long as people burnt wood they scarcely needed chimneys, but coal introduced chimneys, to say nothing of steamboats and railroads. The Archbishop of Canterbury, who at that time used to reside alternately at Croydon and at Lambeth, had by royal permission thirty cartloads of “sea-borne coal” annually delivered at his archiepiscopal palace, because, says the historian, “for his own private use in his own chamber he now had the convenience of chimneys.”

The smoke nuisance of that day deserves a passing notice. Smoke was then with many a grand luxury. Old Hollingshed says, “Now we have many chimneys, yet our tenderlings do complain of rheums, and catarrhs, and poses. Once we had nought but rere-doses,[58]and ourheads did never ake. For the smoke of those days was a good hardening for the house, and a far better medicine to keep the good man and his family from the quack or the pose, with which then very few were acquainted. There are old men yet dwelling in the village where I remain, who have noted how the multitude of chimneys do increase, whereas in their young days, there was not above two or three, if so many, in some uplandish towns of the realm, and peradventure in the manor places of some great lords; but each one made his fire against a rere-dose in the hall, where he dined and dressed his meat. But when our houses were built of willow, then we had oaken men; but now that our houses are made of oak, our men are not only become willow, but a great many altogether men of straw, which is a sore alteration.”

Leaving this digression, let us try and get a bird’s-eye view of the coal-fields of the British Isles. If we commence in Devonshire, we find there the Devonian culms, or Bovey Tracey coal, lying near the surface of the ground, and of little except local use. Crossing over the Bristol Channel, we come intoPembrokeshire, to the Welsh basin, remarkable because thence we mostly get our anthracite coal. Thence we pass on to the Derbyshire coal-fields, that go with little interruption into Scotland, averaging 200 miles in length, and about 40 in width,—once mighty tropical swamps, jungles, and forests, now become chief minerals of commerce. Included in this last immense field is the great Newcastle coal district, the most celebrated of any, supplying almost all the south of England, and nearly all London, with their best coals; and the Scotch carboniferous system, celebrated for its numerous fossils, and for its general base of old red sandstone. In addition to which there is the Irish carboniferous system, occupying as much as 1,000 square miles, but of an inferior quality, and not likely to be of any great economical importance.

In the words of Professor Ansted, we add: “This account of the coal-beds gives a very imperfect notion of the quantity of vegetable matter required to form them; and, on the other hand, the rate of increase of vegetables, and the quantity annually brought down by some great rivers both of the eastern and westerncontinents, is beyond all measure greater than is the case in our drier and colder climates. Certain kinds of trees which contributed largely to the formation of the coal, seem to have been almost entirely succulent,[59]and capable of being squeezed into a small compass during partial decomposition. This squeezing process must have been conducted on a grand scale, and each bed in succession was probably soon covered up by muddy and sandy accumulations, now alternating with the coal in the form of shale and gritstone. Sometimes the trunks of trees caught in the mud would be retained in a slanting or nearly vertical position, while the sands were accumulating around them; sometimes the whole would be quietly buried, and soon cease to exhibit any external marks of vegetable origin.”[60]

There are various kinds of coal on which we may bestow a few words. There isanthracite, or non-bituminous coal, and which, therefore, burns without flame or smoke, and is extensively used in malting; andsea-coal, which is highly bituminous, and which gives forth somuch flame and smoke, that in the good old times of 1306, Parliament forbad its use in London by fine and by demolition of all furnaces in which it was burnt, because “this coal did corrupt the air with its great smoke and stink;” andcannel-coal, the etymology of which, they say, is firm the word candle, because in many parts of Lancashire the poor use it in place of oil or tallow for lights; andjet, sometimes called black amber, which in France employs about 1,200 men in one district, in making earrings, rosaries, and other ornaments; and last of all, there is wood passing into coal calledlignite, found only in the Devonshire culms.

Having thus glanced at the natural history and varieties of coal, we may here try and realize the flora of the carboniferous era. An examination of the fossils of this period enables us to come to undoubted conclusions concerning the trees and plants of that era, so that it is no mere dream to look upon a picture like the following, and see in it a landscape of the coal-forming time of the British islands.

FLORA OF THE COAL MEASURES RESTORED.

The sun then poured down his golden beams of heat and light, and a tropical climate prevailed in our now cold and humid England. The mountain tops were gilded with his rays; a vast ocean studded with islands, and these crowned with gigantic palms and ferns, then covered our northern hemisphere. In that ocean but few fish were to be found, though many rare molluscous animals swam to and fro, enjoying their brief term of life, and discharging all their appropriate functions. Mountain streams discharged their muddy waters into this ocean, leaving along their margin course broken trees, vegetables, grasses and ferns. The giant Lepidodendron looked like a monarch of the ancient world, while around him smaller ferns, vying with each other in beauty and grace, grew, “first the blade” and then the ripened frond, until, in obedience to the great law of organic life, they died and decayed, and became material for the coming man’s future use. But amidst all this prodigal luxuriousness of the vegetable world, there appears to have been neither bird nor beast to break the monotony of the scene; all was silent as the grave—rank, moist verdure below; magnificent ferns and palms above, and the stillness of death on every side.[61]

Fossil

Let us, however, glance at the principal ferns, whose fossil remains we have often found at the mouth of many a coalpit thrown out among the waste. The uncouth names given to them, uncouth only in appearance, must not deter the reader from his acquaintance with their peculiarities; for are not the names of botanical science almost, if not quite, as repellent at first? This star-shaped beauty, (1) theasterophyllite, (fromaster, a star, andphyllon, a leaf,) was a common one;this (2) is thesphenopteris(fromsphēn, a wedge, andpteron, a wing), so named from a fancied resemblance of the petals of the frond to a wedge; the next (3) is thepecopteris(frompekos, a comb, andpteron, a wing), from a resemblance of the frond to the teeth of a comb; the next (4) is theodontopteris(fromodous, a tooth, andpteron, a wing), and in this the frond is something like the jaws of a shark bound together by a central stem, from which they diverge; and the last (5), our favourite, is theneuropteris(fromneuros, a nerve, andpteron, a wing), on account of the exquisite beauty with which the fibres, like nerves, distribute themselves.

“Besides the ferns, then growing to a great size, there were other plants whose modern representatives are uniformly small; but as the resemblance in this case is simply one of general form, and the great majority of other trees seem to possess no living type to which they can be referred, it is by no means impossible that these also may be completely lost. One example of them is seen in a plant, fragments of which are extremely common in the coal measures, and which has been calledcalamite.[62]The remains of calamites consist of jointed fragments, which were originally cylindrical, but are now almost always crushed and flattened. They resemble very closely in general appearance the common jointed reed, growing in marshes, and calledequisetum, or mare’s tail; but instead of being confined to a small size, they would seem to have formed trees, having a stem more than a foot in diameter, and jointed branches and leaves of similar gigantic proportions. They were evidently soft and succulent, and very easily crushed. They seem to have grown in great multitudes near the place where the coal is now accumulated; and though often broken, they seldom bear marks of having being transported from a distance.”[63]The fossils of the carboniferous system here figured we found not long since in the neighbourhood of Stockport.

CALAMITES.

CALAMITE.

STIGMARIA FICOIDES.

This chapter on the carboniferous system must not be further lengthened. We do not aspire to teach the science of geology; we aim only to impart such a taste for it as shall lead the reader to consult our master works on this subject, and if we succeed in this humble but useful aim, our purpose will be fully answered. Only in reference to the economic uses of coal, we will quote the following, copied, we believe, fromthe “Athenæum” some time since, but unfortunately copied without reference to its original; a lesson for common-place-book keepers. The writer in speaking of coal-gas says: “The consumption of gas is enormous. The following statistics give us an insight into the extent which this branch of industry has attained. In England 6,000,000 tons of coals are annually employed for the manufacture of gas, and from 12,000,000 to 15,000,000 pounds sterling expended in its production. In London alone 500,000 tons of coals are annually used, producing 4,500,000,000 cubic feet of gas, and 500,000 chaldrons of coke; of the latter, 125,000 chaldrons are consumed in manufacturing the gas, and the remainder sold for fuel. Upwards of half-a-million houses in London burn gas, and the length of the main arteries for conveying it is 1,600 miles. The capital employed in the metropolis is 4,000,000l.The manufacture of coal-gas for the purpose of illumination affords one of the most striking instances of the triumphs of science when enlisted in the divine cause of civilization. Looking at it as a whole, and regarding the ingenuity evinced in the construction of apparatus, the chemical skill and beauty displayedin the process, and the very valuable purposes to which it is applied, it forms one of the most beautiful, curious, and useful of our manufactures; and probably there is no subject of a manufacturing character in the present day which more engages public attention, coal-gas having now become not a mere luxury, or even convenience, but an absolute necessary. In the words of my late colleague and friend, Dr. Hofmann, ‘The extent to which the use of gas has affected the arts and manufactures in this country, can only be conceived by those who are aware of its innumerable applications in the double capacity of giving light and heat. To our experimental chemists the benefits afforded by gas cannot be overrated, more especially in England, where the price of spirits of wine is so exorbitant. But for the use of gas in the laboratory, the progress of chemistry in this country must have been greatly retarded.’

“In speaking of the general influence of the manufacture of coal-gas, it is impossible to leave unnoticed the number of hands daily engaged in raising whole strata of coal, in loading and navigating the fleets employed in conveying it, not only to the different parts of this kingdom,but to foreign countries, which consume a larger quantity of English coal for the production than is generally known. The extension of the gas enterprise produced a sensible effect on the ironworks, by the vast number of retorts, the stupendous gas-holders, and endless pipes required for generating, storing, and conveying it.

“Several other branches of trade were also forced into increased activity, and even new trades sprung up in consequence of the extended use of gas. The substances produced in the purification of gas naturally attracted the attention of the gas manufacturer; and chemistry soon pointed out valuable purposes to which they might be applied. The oily matter, which separates as a secondary product in the distillation of coal, yielded, when purified in its more volatile portion, the most convenient solvent for caoutchouc; another part of it was found to be an efficient preservative of timber, and the pitchy residue formed the chief ingredient of an excellent substitute for the flag stones of our pavements; while the ammoniacal liquors were found useful in improving the fertility of land. Thus, after the lapse ofcountless ages, was the nitrogen of petrified fern forests resuscitated in the ammoniacal liquors of the gas-works, to vegetate once more and increase the produce of our corn fields.”

SIR HUMPHREY DAVY’S LAMP, AND MINER AT WORK.

“All nature feels the secret power,And through eternal change obeysUp from the deepest region creepsThe trace of life of former days.”Faust.

“All nature feels the secret power,

And through eternal change obeys

Up from the deepest region creeps

The trace of life of former days.”

Faust.

Back to Index Next