The Age of Coal—Plants of the Carboniferous Age—Hugh Miller’s Description of a Coal Forest—Vast Time required for the Formation of the Coal-fields—Derangements and Dislocations—Faults—Their Disadvantages and Advantages—Bituminous Coals—Anthracites—Our Black Diamonds—Advantageous Position of our Coal Mines—The South Welsh Coal-field—Great Central and Manchester Coal-fields—The Whitehaven Basin and the Dudley Area—Newcastle and Durham Coal-fields—Costly Winnings—A Ball in a Coal-pit—Submarine Coal Mines—Newcastle View from Tynemouth Priory—Hewers—Cutting Machines—Putters—Onsetters— Shifters—Trapper Boys—George Stephenson—Rise of Coal Production—Probable Duration of our Supply—Prussian Coal Mines—Belgian—Coal Mines in various other countries—Maunch Chunck.

The history of the primitive races of mankind, as far as we are able to trace it in the few relics that have survived their existence, shows us that an age of stone was followed by one of bronze, which in its turn was succeeded by one of iron. The Golden Age has probably never existed but in the fancy of poets who sought in the land of dreams a compensation for the deficiencies of the real world; and there can be no doubt that, despite California and Australia, our own times are as far from realising the pleasing vision as any before them.

But a title to which they have a better claim is founded upon the vast use of the mineral fuel without which the glorious inventions of Watt and Stephenson would have been comparatively vain; and whoever has attentively examined the foundations of our industry, our commerce, our wealth, and our civilisation will hardly deny that we live in what may justly be termed the Age of Coal.

This mineral, the importance of which in the political economy of the leading nations of the globe can hardly be overrated, is also one of surpassing interest in a geological point of view, for the history of its formation is one of the great marvels of the subterranean world.

The plants whose growth and decay originally furnished the materials of which our black coal^[63] is composed, flourished in that far distant period when as yet no bird or mammalian quadruped had made its appearance, when even the gigantic Ichthyosaurus was not yet born, and the progress of organic life had not advanced beyond the creation of some uncouth reptiles or strangely formed fishes. From the vast space of time which separates us from the carboniferous age, it may easily be imagined that the state of the vegetable world was then extremely different from that now prevailing. The vegetable remains which constitute coal have generally been so transformed as to afford no trace of their original texture; yet the distinct plants found here and there preserved in the mass, and which amount to about five hundred species, plainly bear the character of a swampy vegetation, and show that they must have grown in submerged, or at least extremely humid, situations. They consist chiefly of ferns, of Lepidodendra, allied to the club-mosses of the present day, of a few coniferous trees, the woody structure of some of them showing that they were related to the Araucarian division of pines, more than to any of our common European firs; of some large ‘horsetails,’ and of SigillariÆ and Calamites, that seem to have been distinct from all tribes of now existing plants. Scanty as are these relics of an extinct world, they yet allow the fancy to reconstruct the forests of which they formed a part, and to wander through those dismal woods where generations after generations of arborescent ferns and moor-plants flourished and decayed for the use of beings that were to appear millions of years later upon the stage of life.

The following description by Hugh Miller will assist our fancy in roaming among the primeval thickets from which coal was formed: ‘We have before us a low shore, covered with a dense vegetation. Huge trees of wonderful form stand out far into the water. There seems no intervening beach. A thick hedge of reeds, tall as the masts of pinnaces, runs along the deeper bays, like water-flags at the edge of a lake. A river of vast volume comes rolling from the interior, darkening the water for leagues with its slime and mud, and bearing with it to the open sea reeds and ferns and cones of the pine, and immense floats of leaves, and now and then some bulky tree undermined and uprooted by the current. We near the coast, and now enter the opening of the stream. A scarce penetrable phalanx of reeds, that attain to the height and wellnigh to the bulk of forest trees, is ranged on either hand. The bright and glossy stems seem rodded like Gothic columns; the pointed leaves stand out green at every joint, tier above tier, each tier resembling a coronal wreath, or an ancient crown with the rays turned outwards, and we see atop what may be either large spikes or catkins. What strange forms of vegetable life appear in the forest behind! Can that be a club-moss that raises its slender height for more than fifty feet from the soil? Or can these tall palm-like trees be actually ferns, and these spreading branches mere fronds? And then these gigantic reeds! are they not mere varieties of the common horsetail of our bogs and marshes, magnified some sixty or a hundred times? Have we arrived at some such country as the continent visited by Gulliver, in which he found thickets of weeds and grass tall as woods of twenty years’ growth, and lost himself amid a forest of corn fifty feet in height? The lesser vegetation of our own country, its reeds, mosses, and ferns, seems here as if viewed through a microscope, the dwarfs have sprung up into giants, and yet there appears to be no proportional increase in size among what are unequivocally its trees. Yonder is a group of what seem to be pines—tall and bulky, ’tis true, but neither taller nor bulkier than the pines of Norway and America. There is an amazing luxuriance of growth all around us. Scarce can the current make way through the thickets of aquatic plants that rise thick from the muddy bottom; and though the sunshine falls bright on the upper boughs of the tangled forest beyond, not a ray penetrates the more than twilight gloom that broods over the marshy platform below. The rank steam of decaying vegetation forms a thick blue haze, that partially obscures the underwood. Deadly lakes of carbonic acid gas have accumulated in the hollows; there is a silence all around, uninterrupted save by the sudden splash of some reptile fish that has risen to the surface in pursuit of its prey, or when a sudden breeze stirs the hot air, and shakes the fronds of the giant ferns, or the catkins of the reeds. The wide continent before us is a continent devoid of animal life, save that its pools and rivers abound in fish and mollusca, and that millions and tens of millions of the infusory tribes swarm in the bogs and marshes. Here and there, too, an insect of strange form flutters among the leaves. It is more than probable that no creature furnished with lungs of the more perfect construction could have breathed the atmosphere of this early period and have lived.’

As coal seams have been discovered as far to the north as Greenland, Melville Island, and Spitzbergen, where now no trees will grow, it has been inferred that, in the primeval ages which witnessed their birth, a tropical climate must have reigned over the whole surface of the earth; but the vegetation of arborescent ferns does not necessarily imply a very warm climate, as such plants are found to flourish in New Zealand, together with many conifers and club-mosses, so that a forest in that temperate country may make a nearer approach to the carboniferous vegetation than any other now existing on the globe. So much is certain, that a very different distribution of sea and land must in those times have mitigated the severity of the Arctic winter, or, perhaps, as Professor Oswald Heer conjectures, our solar system may then have rolled through a space more densely clustered with stars, whose radiant heat gave to our earth the advantage of a mild climate, even at the poles.

The space of time required for the formation of the coal-fields is as immeasurable as the distance that separates us from Sirius. We know by experience how thin the sheet of humus is which the annual leaf-fall of our trees, or the yearly decay of our moor-plants, leaves behind, and how many decenniums must elapse before one single inch of solid mould is formed. But there are many coal strata eight, ten, or even forty or fifty feet thick; and if we consider besides the mighty pressure of the superincumbent rocks which store them in the smallest compass, we cannot possibly doubt that one such stratum must have required thousands of years for its formation. Our wonder increases when we reflect that in many coal-measures (the series of beds intimately associated with the seams of coal) no less than a hundred thick and thin seams of coal alternate with layers of sandstone and shale, so that the reckoning would swell to millions were we able to fathom the ages of their successive growth.

It may well be asked how such vast masses of vegetable origin, which required the sun’s light for their formation, came thus to be incased in stone thousands of feet beneath the surface of the earth? More than one theory has been advanced to solve this difficult problem, which can hardly be explained in any other manner than by a general, slowly progressing subsidence of the humid lowlands, alternating with periods of rest. Fancy a wide delta land, similar to Egypt or the Netherlands, covered with luxuriant forests, whose spoils, accumulating where they fall, form in the course of centuries a thick stratum of vegetable matter. This land then sinks, suddenly or gradually, under water, many a fathom deep, and remains there perhaps for ten thousand years, till a vast deposit is formed of sandstone and shale, brought down from the highlands by the rivers that come rolling from the interior, the pressure of which, aided by water, converts the stratum of wood into coal. By this deposit the bottom is gradually filled up, and the bay again converted into marsh or meadow, upon which again vegetation flourishes for a thousand years till the materials of a second bed of coal are collected. A third submergence takes place, rocky strata are again deposited, the water again shoals into land capable of bearing plants, a third period of forests commences, and continues till the mass of vegetable matter destined to form a new bed of coal is accumulated. It is unnecessary to pursue the series any further; let it suffice to say that in this manner coal followed upon sand, or sand upon coal, till in the carboniferous basin of Nova Scotia, for instance, a vertical subsidence of three miles was gradually filled up by the waste swept down from the higher lands, or by the accumulation of vegetable matter.

Great as are these changes of level, they do not indicate any more considerable or violent perturbations than those which take place at the present day, either from earthquakes or from slow oscillations of the soil. Large areas in the Pacific and elsewhere are known to be actually subsiding at the rate of three or four feet in the century, and when measured on the scale of geological time, the depression which sunk the first carboniferous forests of South Wales or Nova Scotia to the depth of ten or twenty thousand feet, probably proceeded at the same slow rate. Adding to these vast epochs of gradual subsidence the long periods of rest which intervened between them, it is perhaps no exaggeration to affirm that several millions of years may have been required for the formation of a coal-field such as that of SaarbrÜcken or South Wales. The fossil remains inclosed in the various layers of the carboniferous beds alone suffice to prove the immensity of time required for their accumulation, for the species of ferns or lycopods imbedded in the lower seams of a coal-field are found gradually to disappear in the higher ones, while new species are continually appearing on rising in the series, until, finally, the plants of the older seams have completely made way for newer forms. Thus the coal formation has, during the vast ages of its growth, changed more than once the aspect of its flora, and the plants which flourished in its youth had long since disappeared from the earth when it approached its end.

Although all coal-fields must have originally been formed in horizontal or slightly undulating situations, yet in many cases they have undergone enormous derangements or dislocations from subsequent terrestrial changes; and to this circumstance is mainly due their utility to man. Had they been permitted to remain in their primitive geological position, we probably should never have enjoyed the benefit of the coal, because it would have been too deep for our reach. We might have known it to be there, but it would have been beyond our power to pierce a mile or two into the earth. But, by a wonderful and merciful providence, the oscillations to which the earth-rind is subject, have frequently upheaved them enormously out of their original positions; and the elevated portions having often been denuded by water, large patches of coal have thus been rendered available to man.

The various subterranean changes which have acted upon the coal-fields during the course of unnumbered ages have not only raised or sunk, but frequently dislocated, contorted, ruptured, or broken them up in a most extraordinary manner. In the coal-field near Mons, in Belgium, for instance, a vast lateral pressure has curved the strata again and again, and even folded them four or five times into zigzag bendings, so that on sinking a shaft the same continuous layer of coal is cut through several times.

Frequently a concave form has been the result of these terrestrial revolutions, and hence coal-fields are often called coal-basins. Thus, in the coal-field south of Malmesbury, the strata appear to dip from the surface, and rise again to it after attaining a certain depth, so that a section of them suggests the idea of a boat or basin.

Very commonly one portion of a continuous stratum or series of strata has been broken away from the rest, and has been displaced, either by elevation or depression, or shifting on one side, for various distances. The amount of displacement is sometimes only a few inches, and at other times several hundred fathoms, and the extent may be twenty yards or twenty miles.

We may easily conceive the difficulties which these disruptions frequently throw in the way of the miner, who in following what he considers a valuable seam of coal is suddenly stopped by coming in contact with a fault, a trouble, or a slip, as these phenomena are expressively called, and finds the coal shifted several yards above or below, or even completely lost. On the other hand, the miner, thus provokingly stopped in his labours, must not forget that it is perhaps owing to the very shifts he complains of that the outcrop of the coal has occurred at all in his neighbourhood, and that the coal is workable throughout a very large portion of the district in which he is interested.

A most important advantage is also derived from the existence of these numerous faults in coal strata; namely, that they intersect a large field of coal in all directions, and by the clayey contents which fill up the cracks accompanyingaccompanying minor faults, they become natural coffer-dams, which prevent the body of water accumulated in one part of the field from flowing into any opening which might be made in it in another part. A remarkable instance of the advantage arising from the presence of a great line of fault occurred in the year 1825 at Gosforth, near Newcastle, where a shaft was dug on the wet side of what is locally termed the Great Ninety Fathom Dyke, which there intersects the coal-field. The workings were immediately inundated with water, and it was found necessary to abandon them. Another shaft, however, was sunk on the other side of the dyke, only a few yards from the former, and in this they descended nearly 200 fathoms, or 1,200 feet, without any hindrance from the water.

The separation of a coal-field into small areas by dykes or faults is likewise very beneficial in case of fire in a coal-pit, for in this case the combustion is prevented from spreading widely, and destroying, as it otherwise would, the whole of the ignited seam.

‘The natural disposition of coal in detached portions,’ says the author of an excellent article in the Edinburgh Review,^[64] ‘is not simply a phenomenon of geology, but it also bears upon national considerations. It is remarkable that this natural disposition is that which renders the fuel most accessible and most easily mined. Were the coal situated at its normal geological depth, that is, supposing the strata to be all horizontal and undisturbed or upheaved (sic), it would be far below human reach. Were it deposited continuously in one even superficial layer, it would have been too readily, and therefore too quickly mined, and all the superior qualities would be wrought out, and only the inferior left; but as it now lies, it is broken up by geological disturbances into separate portions, each defined and limited in area, each sufficiently accessible to bring it within man’s reach and labour, each manageable by mechanical arrangements, and each capable of gradual excavation without being subject to sudden exhaustion. Selfish plundering is partly prevented by natural barriers, and we are warned against reckless waste by the comparative thinness of coal-seams, as well as by the ever-augmenting difficulty of working them at increased depths. By the separation of seams one from another, and by varied intervals of waste sandstones and shales, such a measured rate of mining is necessitated as precludes us from entirely robbing posterity of the most valuable mineral fuel, while the fuel itself is preserved from those extended fractures and crumblings and falls which would certainly be the consequence of largely mining the best bituminous coal, were it aggregated into one vast mass. In fact, by an evident exercise of forethought and benevolence in the Great Author of all our blessings, our invaluable fuel has been stored up for us in deposits the most compendious, the most accessible, yet the least exhaustible, and has been locally distributed into the most convenient situations. Our coal-fields are, in fact, so many bituminous banks, in which there is abundance for an adequate currency, but against any sudden run upon them nature has interposed numerous checks, by locking up whole reserves of the precious fuel in the bank cellar, under the invincible protection of ponderous stone-beds.’

If we examine the nature of the mineral fuel thus provided for us in the bowels of the earth, we find a number of varieties greatly differing from each other in chemical composition and in combustible value. Thus the anthracites or non-bituminous coals, which contain from eighty-five to ninety-seven per cent. of pure carbon, are not easily ignited, and yield no flame and but little or no smoke.

The bituminous coals, on the contrary, contain a large proportion of volatile matter, amounting to as much as thirty, forty, or fifty per cent., and are consequently very inflammable, burning with a bright flame, considerable smoke, and a penetrating odour.

But as Nature in general does not love those sharp divisions to which theorists are so partial, thus also there is no fixed boundary between these two classes of mineral fuel; and we find an uninterrupted series of intermediate qualities between pure anthracite and the fattest coal.

It may be remarked that if coal were of one uniform chemical composition, its utility would be confined within narrower limits, as the bituminous, semi-bituminous, and anthracital varieties have each their distinguishing properties which adapt each to special uses. Some kinds, from their richness in volatile bituminous matter, are excellent for the manufacture of illuminating gas, while, from their smaller proportion of carbon, they could hardly be used for the making of iron; and the anthracites, which yield little or no gas, are very serviceable for smelting or domestic purposes.

It appears from the researches of modern chemistry that the different varieties of coal are due to the progress of decomposition which wood and vegetable matter undergo when buried in the earth, exposed to moisture, and partially or entirely excluded from the air. Slowly evolving carbonic acid gas, and thus parting with a portion of their original oxygen, they become gradually converted into lignite or wood-coal, which contains a larger proportion of hydrogen than wood does. A continuance of decomposition changes this lignite into common or bituminous coal, chiefly by the discharge of carburetted hydrogen, or the gas by which we illuminate our streets and houses; and bituminous coal still continuing to evolve its volatile matter, not only after its being covered with strata thousands of feet in thickness, but even to the present day (as the fire-damp sufficiently proves) is thus ultimately transformed into anthracite, to which the various names of splint-coal, glance-coal, hard-coal, and culm have been given.

When we consider the manner in which coal has been formed in swampy lowlands, or more particularly in river-deltas, which gradually subsided to a considerable depth beneath the level of the sea, we cannot wonder that, when compared with the whole extent of the globe, the area of the coal-fields is extremely limited, and confined to but a few favoured countries. In our times delta lands occupy but a small part of the continents and large islands, and there is no reason to suppose that they were more considerable during the carboniferous age, or at any other epoch. Besides, many of the ancient deltas, probably, never subsided at all, so that no coal could be formed on their site; and others, where coal strata were gradually piled up, may still be whelmed beneath the sea awaiting some future upheaval to become serviceable to future generations of man.

After the preliminary remarks on coal and the coal formation in general, I will now briefly describe the chief coal-producing countries of the globe. First on the list stands Great Britain, whose pre-eminence in industry and commerce is entirely founded on her vast deposits of coal. It is this invaluable mineral which sets those countless steam-engines in motion that perform the labours of a hundred millions of men; which spins and weaves the cotton of America, the silk of China, the wool of Australia, and the flax of Belgium into that amazing variety of tissues that serve to clothe almost all the nations of the globe; and which finally produces a greater quantity of the cheapest iron than the combined efforts of all the world. Thus our coals may well be called our black diamonds, and the comparison is indeed paying the latter too high a compliment, for larger masses of diamonds would be utterly worthless, while, by means of our coal, we are able to enjoy the produce of every zone.

Not only do our fifty-one coal-fields surpass in magnitude those which are disseminated over a far greater territory in Germany, Belgium, and France; but their local distribution and geological formation are as favourable as could possibly be wished. Furthest north we see the considerable deposits of Scotland extending from the coast of Fife to the valley of the Clyde. It is to them that Glasgow owes its half-a-million of inhabitants, and a wealth far surpassing that of all Scotland under the reign of ‘bonnie’ Queen Mary. In England, north of the Trent, along the Wear and Tyne, and even extending far beneath the sea, we have the coal-fields of Northumberland and Durham, with Cumberland and those of Yorkshire, Nottinghamshire, and Derbyshire. After these comes the large field of Lancashire, or, as it is sometimes named, the Manchester Coal-field. Looking to the central districts, we see the coals of North and South Staffordshire and of Leicestershire. In the north-west we have the field of North Wales; in the more central west, the deposits of the Plain of Shrewsbury, Coalbrook Dale, and the Clee Hills; and in the south-west, the great coal-field of South Wales, and the minor ones of the Forest of Dean, of Somersetshire, and of Gloucestershire.

The inspection of a good geological map shows us at once how advantageously for commerce these several coal-stores are distributed. Every large coal-field in England and Scotland is hardly ever distant more than thirty miles from the next, so that from the Clyde to Somersetshire the whole interior of the country can easily, by means of canals and railroads, be provided with fuel. The east and west coasts of the land are nowhere above fifty miles from a coal-field; and even the most remote localities in the three kingdoms are able to provide themselves from distances within 150 miles.

But it is chiefly the neighbourhood of the sea which gives such an incomparable value to our most important coal-fields; as, thanks to this advantageous situation, which none of the French, Belgian, and German coal-fields possess, Great Britain is enabled to provide not only her own coast-towns, but almost all the sea-ports in the world, with a cheaper fuel than can be produced in their own country. Even in Ostend, Belgian coal, rendered dear by canal transport, is unable to compete with that which is brought over sea from England; and Hamburg provides herself with fuel from Newcastle and Hartlepool, and not from the coal-fields of Saxony and Westphalia.

Coal is found in seventeen counties in Ireland, over an area of about 3,000 square miles. Yet, notwithstanding this great abundance of coal which the country possesses, and which is distributed throughout almost all parts of the island, from Limerick to Antrim, her capital and chief cities and ports have hitherto depended upon Great Britain for their supplies of mineral fuel, both for domestic and for manufacturing purposes. To those who are unacquainted with the actual circumstances, it appears scarcely credible that this fine country has made so little use of the coal which has been so bountifully bestowed upon her. Among other causes not political, which perpetuate this state of things, is the extraordinary facility and cheapness with which the ports of Ireland can be supplied from the great western coal-fields of Great Britain. The excellence, abundance, and cheapness of peat, which is not only the common fuel of the poor in the interior, and, indeed, of all classes in some districts, but is also brought in barges by the great canal, and consumed to a considerable amount in the capital itself, is another reason why the Irish coal-mines have, as yet, been so little worked.

When we consider the vast importance of coal, we cannot wonder at the paramount influence which it has exercised over the distribution of our population in modern times. While Salisbury, Winchester, and Canterbury—important towns of mediÆval England—are reduced to atrophy from the distance and absence of coal-fields, Newcastle, Leeds, Manchester, Sheffield, Birmingham, Glasgow, and a host of other flourishing towns may truly be said to be built on coal.

Where there are large coal-fields there is life and a prospect of almost unlimited prosperity, for they are sure to attract machinery and man. Take a geological map of a new and thinly-populated country; and if it be marked with coal-fields the spots where large cities will exist hereafter may be safely determined.

A more detailed examination of the chief coal-fields of England shows us the immensity of the mineral riches which are here still hoarded up for the benefit of future generations.

The superficial extent of the South Welsh coal-fields is about a thousand square miles. On its northern wing we find on an average twenty-one coal bands, forming an aggregate thickness of eighty and a half feet. In some parts of the south wing there are even as many as thirty-three bands of an aggregate thickness of one hundred and four feet of pure coal, so that the average depth of the field may be estimated at ninety-two feet.

Numerous transversal valleys intersect this magnificent coal-field, and afford the easiest means of working it in every depth. They also facilitate the transport of the coal on the canals and railroads which lead along their bottom or along their slopes to the harbours of the Bristol Channel. In the chapters on iron and copper, I have had occasion to describe the gigantic industries, founded on these natural advantages, which have raised South Wales from being one of the most insignificant into one of the most important provinces of the empire.

All the coals of this basin are so rich in carbon as to yield from seventy to ninety per cent. of coke. They are either anthracites or only semi-bituminous, and are consequently not suitable for making gas, nor are they much liked for burning in open fire-places, as they do not emit a genial flame. On the other hand, the semi-bituminous Welsh coal is invaluable for burning in steam-engines, for it has been proved to generate one-quarter more steam than any other kind of English coal. One of its properties—by no means unimportant—is its non-liability to spontaneous combustion, which, it is well known, occasionally takes place with bituminous coals, and by which vessels have been lost at sea, and warehouses ignited on land. The value of the Welsh steam or slightly bituminous coal is enhanced by its quality of burning almost without smoke, a property hitherto slightly appreciated, but the importance of which in time of war is evident. Steamers burning the fat, bituminous coal can be tracked at sea at least seventy miles, before their hulls become visible, by the dense columns of black smoke pouring out of their pipes or chimneys, and trailing along the horizon. It is a complete tell-tale of their whereabouts, which is not the case with vessels burning Welsh or anthracital coal. From its compactness and density, the latter has likewise great advantages in point of stowage space over the ordinary weak bituminous coals. For long voyages this concentration of power and economy of space may easily be appreciated. From its great superiority over other kinds, Welsh coal has been exclusively used for some time past by the French Government, and it is also employed in England by all the chief mail packet companies.

Coal is not exported from the South Wales basin as much as from some other fields, owing to the enormous requirements of the large iron works, most of which consume as much as can be supplied by their collieries. Every week, however, sees increased supplies of Welsh coal thrown into the London market, and every year fresh collieries are opened to meet the demand. The total number of pits in South Wales in 1865 was four hundred and eighteen, which produced between seven and eight million tons annually. The New Navigation Pit at Mountain Ash may be cited as an example of the grand scale on which the most important of these workings are conducted. The shaft is eighteen feet in diameter inside the walling, and divided into four compartments, two of which are for the drawing of coal, one for sending the workmen up and down, and the fourth for the drainage. Notwithstanding the great depth of three hundred and seventy yards, a carriage containing two half-tons of coal can be wound up in one minute, and the whole colliery is estimated to supply more than one thousand tons a day. The mineral property extends over an area of seven miles long by three miles in width, covering from four thousand to five thousand acres of four-foot coal. From this one case the reader may form a slight estimate of the boundless resources of the whole basin.

The Great Central Coal-field, which ranges through South Yorkshire, Nottinghamshire, and Derbyshire, has a superficial extent of about one thousand square miles. In character it is closely allied to that of Newcastle, and is considered by some geologists to be a re-emergence of the same strata from beneath the covering of the magnesian limestone under which they suppose it to be concealed through the intervening space. It extends a little from the north-east of Leeds nearly to Derby, a distance of more than sixty-five miles. Its greatest width—twenty-three miles—is on the north, reaching nearly to Halifax on the west. On the south it extends towards the east to Nottingham, and is there about twelve miles wide. Though possessing some fine coal-seams, it is of far inferior importance to the Manchester or South Lancashire Coal-field, from which it is separated by a lofty chain of hills. This highly valuable basin, which extends over about five hundred and fifty square miles, begins in the north-west of Derbyshire, and continues thence to the south-west part of Lancashire, forming an area somewhat in the shape of a crescent, having Manchester nearly in the centre.

Of the smaller coal-fields, the most important are the Whitehaven basin (one hundred and twenty square miles) and the Dudley or South Staffordshire area (ninety square miles) which is particularly valuable for the extensive iron works which it maintains. One portion of this coal-field is distinguished by the presence of one continuous bed of coal thirty feet thick, which for British coal is astonishing; and this mass extends seven miles in length and four in breadth. In this favoured district coal-seams five or six feet thick are called thin seams; in Newcastle they would be called thick seams.

Though not so extensive as the South Welsh area, the coal-fields of Newcastle and Durham are of far more ancient celebrity. Their produce is chiefly shipped on the Tyne, Wear, and Tees, small rivers hardly traceable on a map of the world, and yet far more important to commerce than the mighty Orinoco or the thousand-armed Amazon. This magnificent coal area is bounded on the north by the river Coquet, and extends southward nearly as far as Hartlepool, a distance of about forty-eight miles. Its extreme breadth is about twenty-four miles, and the whole superficial extent may amount to about eight hundred square miles.

There are in all about fifty-seven different seams of coal in the Great Northern Coal-field, varying in thickness from an inch to five feet five inches and six feet, and comprising an aggregate of about seventy-six feet of coal.

The pits are established chiefly with reference to one or more of the three following seams. The most valuable is called the High Main Seam, and is about six feet thick. The next in value is the Bensham Seam, about three feet thick, which is remarkable for its excellent quality as a domestic coal, and for the enormous quantity of gas evolved from it in the mine. The Hutton or Low Main Seam, averaging from three feet six inches to five feet nine inches, is likewise of very good quality, and is extensively worked. It must, however, be remarked that the same seam of coal is not generally valuable in all places. Thus the High Main, which furnishes excellent coal on the Tyne, becomes injured as it proceeds in a south-easterly direction by being intermixed with a band of coal of inferior quality containing iron pyrites, &c.

The Newcastle Coal-field is generally worked at a great depth, an expense of upwards of 50,000l. having in some instances been incurred before the seam of coal was reached which was to reward all this vast outlay and labour. The most remarkable and enterprising work of this kind on record is a sinking at Monk Wearmouth Colliery near Sunderland. After piercing the superincumbent beds of magnesian limestone and lower new red sandstone, the coal strata were reached at a depth of three hundred and thirty feet; but at the same time a spring was tapped which poured water into the workings at the rate of three thousand gallons per minute. This fearful influx was kept under by a steam-engine of two hundred horse-power, and the work was made sure by strong metal tubbing, and carried on successfully, though not without extreme difficulty. On entering the coal measures, however, a new and unexpected check was experienced in the extra thickness of the uppermost coal strata, for which no calculation had been made, and the difficulties were increased when at the depth of one thousand feet a fresh feeder or spring of water was tapped. Additional expense and great loss of time were thus caused; but the proprietors persevered with real Anglo-Saxon pertinacity, undaunted by the apparently hopeless nature of the undertaking, and by the fearful expenses incurred. Success crowned their efforts, and finally, at a depth of 1,710 feet, the Hutton seam of coal was reached, at a cost which, including the necessary preliminary operations, could not have been less than 100,000l.

Another remarkable and costly piece of mining was that of Gosforth Colliery, which lies about three miles north from Newcastle, on the west bank of a romantic ‘dean’ or little valley, through which the Ouseburn winds its way to the Tyne. The sinking was commenced in 1825, and the coal was won on Saturday, January 31, 1829. The High Main coal was reached at twenty-five fathoms below the surface, but near its first appearance the seam was thrown down in an inclined direction by the great Ninety Fathom Dyke which there intersects the coal-field. Hence it became necessary to sink the shaft to the depth of 181 fathoms, in order to come at the level of the lower range of coal. This having been accomplished, a horizontal drift 700 yards long was worked through the face of the dyke to the seam of coal a little above its junction with the dyke. A great part of this excavation had to be made through solid rock. To celebrate the completion of this remarkable work, a grand subterranean ball was given at the very place of triumph, 1,100 feet below the surface of the earth. As the guests arrived at the bottom of the shaft they went to the end of the drift to the face of the coal, where each person hewed a piece of coal as a memento of the day, and then returned to the ball-room, which was brilliantly lit up, and where born-and-bred ladies joined in a general dance with born-and-bred pitmen’s daughters. Between 200 and 300 persons were present, nearly one-half of them belonging to the fair sex. It must be remembered that the pit had not been worked, so that no smoke and dust exuded from its mouth or defiled the ball-room.

Some of the older coal-pits, where excavations have been going on perhaps for a century or more, may be likened to large subterranean cities. The galleries of St. Hilda Colliery, near South Shields, are full seventy miles long; and Killingworth pits are said, on good authority, to have nearly one hundred and sixty miles of gallery excavation.

In some parts the operations of the collier have encroached upon the domains of the ocean. At the Howgill pits, for instance, west of Whitehaven, the excavations have been carried more than 1,000 yards under the sea, and about 600 feet below its bottom. But the most remarkable marine colliery which Great Britain has ever possessed was situated at Borrowstounness. The coal was found to continue under the bed of the sea in this place, and the colliers had the courage to work it half a mile from the shore, where there was an entry that went down into the submarine coal-pit. This was made into a kind of round quay, built so as to keep out the tide which flowed there twelve feet. Here the coals were laid, and a ship of that draught of water could lay her side to the quay and take in the coal. This wonderful pit, which belonged to the Earl of Kincardine’s family, continued to be wrought many years to the great profit of the owners, and the astonishment of all that saw it; but at last an unexpected high tide drowned the whole at once, together with the labourers who were at work. ‘While,’ says the French geologist, Faujas de Saint Fond (who visited this remarkable mine about the end of the last century), ‘the pitmen, by the dismal shine of their lamps, make the deep caverns resound with the blows of their pickaxes, ships driven by a fair wind sail over their heads, and the sailors, rejoicing at the beautiful weather, express their joy in songs: at another time a storm arises; the horizon is in flames, the thunder roars, the sea rages, the boldest tremble; then the pitmen, unconscious of the terrible scene, calmly pursue their labours, and think with pleasure of their homes, while the ship above is shattered to pieces and sinks; unfortunately, but too faithful a picture of the daily changes of human life.’

Nowhere in the world, perhaps, does human activity display a more restless energy than on the site of the Newcastle Coal-field, where, night and day, successive trains heaped with the black diamonds of England speed along far-stretching railways, and hurry down to river and ocean, until they are unloaded and their contents shipped by machinery. Steam-engines are unceasingly at work drawing coals and pumping out water. Thousands of men are underneath our feet cutting down the coal by severe and peculiar labour, while thousands above are receiving the loads and speeding them forwards.

‘Go where you will, there is a network of small railways, leading from pit to pit in hopeless intricacy, but all having a common terminus on the river’s bank or the ocean’s shore. Go where you will, tall chimneys rise up before you, and here and there a low line of black sheds, flanked by chimneys of aspiring altitude, indicates that you are arriving at a colliery. As you draw nearer, men and boys of blackest hue pass you and peer at you with inquiring glances. Now trains of coal-waggons rush by more frequently, noises of the most discordant character increase, and you know that you are at the pit’s mouth, when you behold two gigantic wooden arms slanting upwards, upon which are mounted the pulleys and wheels that carry the huge flat wire ropes of the shaft. For a moment the wheels do not revolve—no load is ascending or descending—but the next minute they turn rapidly, and up comes the load of coals or human beings to the surface. Perhaps the most impressive sight is a large colliery fully engaged at nightwork, with burning crates of coal suspended all around; and after this a view from some neighbouring eminence of all the far-flaming waste coal-heaps, burning up the accumulation of waste and small coal not worth carriage, ever added to the ever-consuming mound, until the whole district appears like the active crater of some enormous volcano.’^[65]

The banks of the Tyne are in many places very high and precipitous, and consequently render peculiar contrivances necessary for the shipping of the coals. The means used for this purpose are various: sometimes inclined tunnels, through which the train of waggons is lowered in chains to the water; sometimes slopes, along which the coals are shovelled into the ship, or still better, the ingenious mechanism of which William Howitt gives us the following description:—

‘As you advance over the plain you see a whole train of waggons loaded with coal, careering by themselves without horse, without steam-engine, without man, except that there sits one behind, who, instead of endeavouring to propel these mad waggons on their way, seems labouring hopelessly by his weight to detain them.

‘But what is your amazement when you come in sight of the river Tyne, and see these waggons still careering on to the very brink of the water!—to see a railway carried from the high bank, and supported on tall piles, horizontally, above the surface of the river, and to some distance into it, as if to allow those vagabond trains of waggons to run right off, and dash themselves down into the river!

SHIPPING COAL.