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The fireside is peculiarly
a British institution, as the people of this country are peculiarly a
home-loving and domestic people. When our countrymen travel abroad, they
uniformly miss the cheerful fireside of their English home, and feel that
the stove, however efficient as a heating apparatus, is a sorry substitue
for the enlivening blaze of a coal-fire, even with the occasional drawback
of a smoky chimney. To an Englishman, the fireside is the emblem of home
comfort. As for our French neighbours, having neither fireside nor home
habits, there is no equivalent term in their language to the English word
comfort. Cowper was the poet of domestic life, and there is nothing finer
in our literature than his tribute to fireside happiness, at the opening
of the "Winter Evening" in "The Task;" and the most charming thing about
it is the homeliness and truthfulness of the picture, which belongs
exclusively to no grade of society, but may, in its essential element, be
realised every winter night in the year, in every well-conditioned
workman's family in the land. Thomas Campbell expressed his admiration for
Cowper's verses in words which render it unnecessary to quote them here,
since the reader can find no stronger inducement to turn up "The Task,"
and peruse, or re-peruse, the passage, than the commendation of one of the
last and best of the British poets. "Of all the verses," says he, "that
have ever been devoted to the subject of domestic happiness, those in his
'Winter Evening,' at the opening of the fourth book of 'The Task,' are
perhaps the most beautiful. In perusing that scene of 'intimate delights,'
'fireside enjoyments,' and 'home-born happiness,' we seem to recover a
part of the forgotten value of existence, when we recognise the means of
its blessedness so widely diffused, and so cheaply attainable; and find
them susceptible of description, at once so enchanting and so faithful."
As we sit absorbed in a
brown study, looking into the parlour fire, and perhaps, like Harley in
the tale, trying to find a body for a Turk's head we have detected amongst
the fantastic shapes of the glowing embers, how rarely does it occur to us
to reflect on the far-seeing wisdom and goodness evinced in preparing the
vast deposits of coal, iron, and other minerals, which minister in such a
remarkable manner to the necessities and comforts of mankind! It was a
striking observation of Playfair's, when speaking of the teachings of
Hut-ton, the founder of the modern geology, that "the mind seemed to grow
giddy by looking so far into the abyss of time; and while we listened,"
said he, "with earnestness and admiration to the philosopher who was
unfolding to us the order and series of these wonderful events, we became
sensible how much further reason may sometimes go, than imagination can
venture to follow." And surely it is fitted to exalt our conceptions of
Divine benevolence to reflect that, throughout the inconceivably remote
and prolonged ages which preceded the appearance of man upon the earth,
and amidst all the amazing vicissitudes and perturbations which have left
their traces upon its surface, creative wisdom was contemplating a
prospective arrangement, so manifestly designed and fitted to promote the
physical prosperity and social progress of the future race of intelligent
beings, as that which has yielded to the successive families of mankind
"the chief things of the ancient mountains, and the precious things of the
lasting hills." If men could perceive these evidences of the goodness of
God and be silent, "the stones would cry out."
The vegetable origin of
coal is no longer a matter of doubt. In the massive deposits of the
carboniferous system are laid up, as in the leaves of a book, the remains
of plants peculiar to the period, many of them unrepresented by any
vegetable forms in the existing flora of the world, although some of them
appear to have resembled the stately tree-ferns of tropical and
extra-tropical countries of the present day. The coal plants flourished in
widely-extended forests of the primeval world, and gradually, as they fell
and decayed, left their remains imbedded in sandstone and shales,
accumulating in lakes and the deltas and estuaries of rivers, to become
altered in the lapse of ages by the united influences of heat and
pressure. The crystalline structure resulting from this combined agency
was unfavourable to the preservation of vegetable tissues; but in selected
specimens prepared for the microscope, the cells and vessels of plants are
distinctly discernible, some of them exhibiting a punctuated or spotted
aspect, proving their affinity to our coniferous woods, such as the modern
araucaria; but ferns are the only plants of the carboniferous era whose
decided relationship to existing members of the same family is clearly
recognisable. No production of the coal-fields is so abundant in the
debris thrown out of the mines, or is met with so frequently in sandstone
quarries in the same system of rocks, as the fossil named stigmaria. This
was long described as a distinct plant, but it is now known to be the root
or creeping stem of sigillaria, so named from the seal-like impressions
left upon its longitudinally-fluted stem, marking where the leaves were
inserted. The sigillaria, with its creeping stem, from its occurring
profusely in all our coal-fields, and from its universal diffusion in
coal-shales throughout the world, is regarded as the most important plant
in the coal formation, as to it we probably owe the largest proportion of
the crystalline mineral. The lepidodendron represents another genus of
coal plants, recognised by the diamond-shaped scars succeeding each other
in a spiral arrangement round the stem. These scaly like marks point out
the position of the lanceolate leaves of the tree, and hence, also, its
name. The effect produced by these spiral scars is highly sculpturesque
and beautiful in some species. Various other vegetable forms occur, but
our space only permits a passing reference to one more, namely, the
calamite, usually found compressed, and resembling, with its furrowed and
jointed stem, the equisetum, or horsetail, of our ponds and ditches. The
beds of shale and sandstone which are intermixed with the seams of coal
often exhibit alternatives of marine and fresh-water fossils, shewing that
the land where the coal plants grew, or the deltas and lakes where their
remains were imbedded, must have repeatedly been submerged beneath the
waters of an estuary or sea, and again elevated to their former level.
From the state of integrity in which many of the plants are preserved,
there is reason to believe that they perished, and were silted up in mud
and sand upon, or near to, the spots where they grew. The strata of the
formation attain a prodigious depth in some coalfields. In South Wales the
beds, according to actual measurement, are of the depth of 12,000 feet.
One acre of coal, three feet in thickness, is estimated to be equal to the
produce of 1940 acres of forest; and in the Scottish coal-fields there are
seams of workable coal, giving an aggregate of 100 to 200 feet in
thickness. When we reflect on the slow and imperceptible process of the
deposition of the rocks from the floating sediment of estuaries and seas,
and take into account the intermediate periods occupied in the growth and
destruction of entire forests of trees, many of them of great magnitude,
the mind is overpowered by the attempt to grasp the idea of the time
occupied in the production of this geological system. Yet the age of
plants had been preceded by two life-periods altogether different, and of
a duration not less prolonged. One era had witnessed the primeval ocean
swarming with zoophytes, crustaceans, molluscs, and vertebrates, whose
fossil remains characterise the Cumbrian and Silurian systems; these had
died and disappeared to give place to the Devonian age, the reign of
fishes, whose marvellous forms are restricted to the period. After the
coal plants had covered immense tracts of the territory which we now
recognise as parts of the old and the new world, an era opened with corals
and crinoids (stone-lilies), occupying the depths of the sea, huge,
frog-like animals crawling on the shore, and coniferous plants reappearing
on the land. The age of reptiles succeeded, and the huge ichthyosaurus and
pleiosaurus swarmed in the Liassic and Oolitic ocean, while the cycas took
its place beside the conifer on the earth. Another revolution, and the
fresh-water of the Wealden period prevailed, with terrestrial and aquatic
reptiles frequenting the rivers and deltas, and new forms of vegetable
life fringing their banks. Then followed the age of the Chalk, with its
profusion of foraminifera, echinoderins, molluscs, fishes, and reptiles.
Nor was it till yet another epoch had come and gone, and another chapter
of the earth's history, recording the annals of the reign of mammalians,
had been written as with a pea of iron on the rocks, that man at length
appeared on the scene, and found a dwelling prepared for him, provided
with every blessing and benefit suited to his physical condition and moral
destiny. But the incalculable ages of geological time, so overwhelming to
the finite minds of the children of a day, are, in the estimate of the
Eternal, but landmarks in the evolution of the plan of creation and
providence. To Him "one day is as a thousand years, and a thousand years
as one day."
The black belts and patches
on a coloured geological map of Great Britain at once indicate the
distribution of the coal-measures and the seats of manufacturing industry.
The silurian hills of the north and the chalk downs of the south of
England; the extensive tracts of gneiss and schistose rocks in the north,
and the Silurians of the south of Scotland, are incapable of affording
employment and subsistence to a numerous population. These districts are
either occupied as the scenes of agricultural labours, or surrendered to
sheep and deer. On the contrary, the central counties of England and
Scotland are also the busy centres of the population. From its proximity
to a mere patch of the English coal-measures, a detached portion, not
exceeding the area of one of the larger Scottish lakes, Birmingham has
risen to the rank of the first iron-manufacturing town in the world.
Manchester and Glasgow have equally derived their manufacturing and
commercial importance from their being placed in the centre of a great
coal basin. The economical and industrial importance of the union of coal
and iron in this island cannot be over-estimated. To their abundance and
accessibility in the deposits of the coal-formation, we owe the growth of
our manufactures, the increase and support of our population, our
wide-spread mercantile enterprise, our rapid intercourse with all parts of
the world, our boundless territories abroad, our opulence and influence at
home. Who can sum up the benefits we derive from coal? It warms and lights
our dwellings, cooks our food, illuminates our streets. Coal develops and
sustains the force which propels the locomotive along the railway and the
ship across the sea; works the printing-press, wields the hammer, lifts
the weight, draws the load, moves the machinery, drives the plough, grinds
the corn, spins the cotton, weaves the cloth, pumps the mine, deepens the
river, covers the land with a network of railways, forges the electric
wire, and, submerging the ocean telegraph, "will throw a girdle round the
earth in forty minutes." Who shall set bounds to the power of coal, iron,
and steam? Miss Martineau lamented, in her journal of Eastern travel, that
the skill which reared the Pyramids of Egypt was amongst the lost arts.
Presently, a civil engineer wrote a letter to the Times newspaper,
offering to accept a commission to build a pyramid equal to the largest,
the loftiest, and the most enduring in the desert of Grand Cairo. His
confidence was in the united power of coal, steam, and iron.
The trees which grew in the
swamps and forests of the coal-period derived their carbonaceous substance
from carbonic acid gas and water, existing in the soil, and floating in
invisible currents in the atmosphere. They imbibed the gas by their
fronds, leaves, and roots; and, separating the solid carbon from the
oxgygen gas, with which it wa3 combined, they appropriated the former for
the purposes of their nourishment and growth, and restored the latter to
the atmosphere. But the plant can only decompose carbonic acid and water
with the aid of the light and heat of the sun; the process ceases in the
dark. In helping the plant to appropriate and deposit carbon in its
tissues, the sun parted with so much of its light and heat, which became
latent in the vegetable. This long-dormant light and heat are set free by
the process of combustion. When the Yule log is laid on the blazing hearth
of the baron's hall, and the faggots are piled on the peasant's fire, they
shed upon the radiant faces of the festive circle light and heat which
were borrowed from the sun, and became latent in the plant, while the seed
sprang into the sapling, and at length became a goodly tree a century or
two old. But the coal glowing in the cheerful fires of our town dwellings,
and diffusing light through the gas-pipes of our streets, is composed of
the relics of vegetables, in which are stored up light and heat derived
from the sunshine of distant ages. In the grate, we liberate this ancient
heat for our comfort; in the gasometer, we take advantage of the light for
our convenience; in our boilers and engines, we convert the latent heat
into mechanical force. And so says a philosopher of our day, young in
years, but mature in thought and observation (Professor William Thomson):—
"Wood fires give us heat and light which have been got from the sun a few
years ago. Our coal fires and gas lamps bring out, for our present
comfort, heat and light of the primeval sun, which have lain dormant as
potential energy beneath seas and mountains for countless ages." |
