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Then recommenced once more the stir and noise of
embarking ; And with the ebb of that tide the ships sailed out of
the harbor, Leaving behind them the dead on the shore, and the village in ruins.
H. W. LONGFELLOW.
XL. - COAL.
1. “You say that coal is transformed vegetable matter, but can you show us how the transformation takes place? Is it possible according to known natural laws ?” The chemist must answer that. And he tells us that wood can become lignite, or wood coal, by parting with its oxygen in the shape of carbonic acid gas or chokedamp, and then common or bituminous coal by parting with its hydrogen chiefly in the form of carbureted hydrogen-the gas with which we light our streets. That is about as much as the unscientific reader need know. But it is a fresh corroboration of the theory that coal has been once vegetable fibre, for it shows how vegetable fibre can, by the laws of nature, become coal. And it certainly helps us to believe that a thing has been done if we are shown that it can be done.
2. This fact explains also why, in mines of wood-coal, carbonic acid — i.e. choke-damp - alone is given off. For in the wood-coal a great deal of the hydrogen still remains. But in mines of true coal, not only is choke
damp given off, but that more terrible pest of the miners, fire-damp or explosive carbureted hydrogen and olefiant gases. Now the occurrence of that fire-damp in mines proves that changes are still going on in the coal; that it is getting rid of its hydrogen and so progressing toward the state of anthracite or culm-stone-coal, as it is sometimes called. In the Pennsylvanian coal-fields, some of the coal has actually done this, under the disturbing force of earthquakes, for the coal, which is bituminous, becomes gradually anthracite.
3. And is a further transformation possible? Yes, and more than one. If we conceive the anthracite cleared of all but its last atoms of oxygen, hydrogen and nitrogen, till it has become all but pure carbon, it would become, as it has become in certain rocks of immense antiquity, graphite, what we miscall black lead. And after that it might go through one transformation more, and that the most startling of all. It would need only perfect purification and crystallization to become — a diamond; nothing less. We may consider the coal upon the fire as the middle term of a series, of which the first is live wood and the last diamond, and indulge safely in the fancy that every diamond in the world has probably, at some remote epoch, formed part of a growing plant. A strange transformation, which will look to us more strange, more truly poetical, the more steadily we consider it.
4. The coal on the fire, the table at which I write, what are they made of ? Gas and sunbeams with a small percentage of ash or earthly salts, which need
hardly be taken in account. Gas and sunbeams. Strange, but true! The life of the growing plant — and what that life is, who can tell ? — laid hold of the gases in the air and in the soil, of the carbonic acid, the atmospheric air, the water, for that too is gas. It drank them in through its rootlets; it breathed them in through its leaf-pores, that it might distill them into sap and bud and leaf and wood. But it had to take in and retain another element without which the distillation and the shaping could never have taken place. It had to drink in the sunbeams, that mysterious and complex force which is forever pouring from the sun and making itself partly palpable to our senses as heat and light. So the life of the plant seized the sunbeams and absorbed them — buried them in itself — no longer as light and heat, but as invisible chemical force, locked up for ages in that woody fibre.
5. So it is. Lord Lytton told us long ago, in a beautiful song, how - The Wind and the Beam loved the Rose.” But nature's poetry was more beautiful than man's. The wind and the beam loved the rose so well that they made the rose, or rather the rose took the wind and the beam, and built up out of them, by her own inner life, her exquisite texture, hue, and fragrance. What next? The rose dies, the timber tree dies, decays down into vegetable fibre, is buried and turned to coal, but the plant cannot altogether undo its own work. Even in death and decay it cannot set free the sunbeams imprisoned in its tissue. The sun-force must stay shut up, age after age, invisible, but strong, working at
its own prison-cells, transmuting them, or making them capable of being transmuted by inan, into the manifold products of coal — coke, petroleum, mineral pitch, gases, coal-tar, benzole, delicate aniline dyes and what-nottill its day of deliverance comes.
6. Man digs it, throws it on the fire, a black deadseeming lump. A corner, an atom of it, warms till it reaches the igniting point — the temperature at which it is able to combine with oxygen. And then, like a dormant live thing, awaking after ages to the sense of its own powers, its own needs, the whole lump is seized, atom after atom, with an infectious hunger for that oxygen which it lost, centuries since, in the bosom of the earth. It drinks the oxygen in at every pore, and burns. And so the spell of ages is broken. The sunforce bursts its prison-cells and blazes into the free atmosphere as light and heat once more, returning in a moment into the same forms in which it entered the growing leaf a thousand centuries since. Strange it is, yet true. But of nature, as of the heart of man, the old saying stands — that truth is stranger than fiction.
XLI. — THE RUNAWAY CANNON.
1. A terrible thing had happened. One of the short cannons of the battery, a twenty-four pounder, had got loose.
This is perhaps the most formidable of ocean accidents. Nothing more terrible can happen to a vessel in open sea and under full sail.
2. A gun that breaks its moorings becomes suddenly a monster. This mass turns upon its wheels, has the rapid movements of a billiard-ball, rolls with the rolling, pitches with the pitching, goes, comes, pauses, seems to meditate, resumes its course, rushes like an arrow from end to end of the ship, circles about, rears, breaks, kills.
3. The mad mass has the bounds of a panther, the weight of an elephant, the agility of a mouse, the obstinacy of an ass, the unexpectedness of the surge, the rapidity of lightning, the deafness of the tomb. It weighs ten thousand pounds, and it rebounds like a child's ball.
4. What is to be done? How to end this ?
A tempest ceases, a wind falls, a leak is stopped, a fire dies out; but how to control this brute of bronze? In what way can one attack it?
How foresee its comings and goings, its returns, its stops, its shocks? One has to deal with a projectile which thinks, which seems to possess ideas, and which changes its direction each instant.
5. The horrible cannon flings itself about, advances, recoils, strikes to the right, strikes to the left, flees, passes,
breaks down obstacles, crushes men like flies. The fault was the chief gunner's. He had neglected to fasten the gun securely in place.
As a heavy wave struck the port, the carronade, weakly attached,