Sinkhole

“ But in the face of the wall, in the bight where the whirlpool turned from it, was a cave the height of a tall man, and some four feet athwart; and below it a ledge, thrust out from the sheer rock and hanging over the terrible water, and it was but a yard wide or so. It was but ten feet above the water, and from it to the grass above must have been a matter of forty feet. But the ness as it thrust forth into the river rose also, so that its crest was a score of feet higher where it went down into the water than its base amidst the green grass. ”

“ On our way back to camp after these first observations I planned a far-and-wide excursion for the morrow. I awoke early, called not only by the glacier, which had been on my mind all night, but by a grand flood-storm. The wind was blowing a gale from the north and the rain was flying with the clouds in a wide passionate horizontal flood, as if it were all passing over the country instead of falling on it. The main perennial streams were booming high above their banks, and hundreds of new ones, roaring like the sea, almost covered the lofty gray walls of the inlet with white cascades and falls. ”

“ But the rain was so violent that my tent was ready to be beaten down with it; and I was forced to go into my cave, though very much afraid and uneasy, for fear it should fall on my head. This violent rain forced me to a new work - viz. to cut a hole through my new fortification, like a sink, to let the water go out, which would else have flooded my cave. After I had been in my cave for some time, and found still no more shocks of the earthquake follow, I began to be more composed. ”

“ The tidal wash, the heavy lapse and then heavier resurge, with the rush and cataract-roar of the seas as they fell far down into the chasm, assailed his ears continuously. Peering down, he could see the foam upon the flood, as it swept ravening round the cave and then fell headlong into the abyss, above which was a misty pulsating whiteness, the send and spray of tons of whirled water. ”

“ March had said,
"Sinks, or sink holes, such as the country to the east of this abounds in, are common to all limestone formations. They are sudden and sometimes very deep depressions or breaks in the surface of the ground, caused by the wearing away of the limestone beneath it by underground currents of water or rivers. In most of these holes standing water of great depth is found, and sometimes swiftly running water. I know several men who have on their places what they call 'natural wells,' or small, deep holes in the ground, at the bottom of which flow streams of water. ”

“ It was a battle between the heavens and the earth,—the stream of molten rock, blinding [Pg 57] hot from the caverns beneath the earth’s crust, meeting the sweet cool waters from the clouds that troop about the mountains or hide their tops in mist and snow. The life-giving flood prevailed over that which brought only defacement and death. The sullen lava flux settled, shrank, and hardened at last, fitting into the granite gorges as melted lead fits the mould into which it is poured. ”

“ Here are cliffs one hundred and fifty feet high, enclosing a basin deep and wide. Immense basaltic columns, perpendicular ranges of rock pillars, rise high above our heads, and from a deep gap, at the head of the gorge, a stream of water rushes out,—an immense volume,—which takes a leap of forty feet or more, and plunges into a rocky basin. It is a most striking picture, this foaming, roaring avalanche of milk-white water, suddenly projected into view from a deep black chasm, and precipitated into this rock-ribbed ravine. ”

“ When the river is in flood, the waterfall, extending from north-west to south-east, has a total width of 1,000 m. There were some picturesque bits of rugged foliated rock over that great staircase, and huge cracks through which the water gurgled and foamed—those fissures formed not by the erosion of water but by volcanic action, perhaps by an earthquake. The large fall to the north-west, over which the water flows in every season, had on one side of it a steep incline, down which we took the canoe until we came to a drop about 15 ft. ”

“ Farther on the cliff sinks to a mere bank, six feet in height, but, whether high or low, you need not fear a surprise by the rising tide, for you can scramble up anywhere out of reach of the water. Looking inland from these points you see always the same character of scenery, and where a path zigzags up you will notice large trays used for carrying up the heaps of pebbles there accumulated, for the construction of drains, fences, and walls. Among remarkable curiosities are two large boulders—one of a slaty rock, the other of granite half embedded in the sand. ”

“ An open ditch cut by the most skillful workman, in the summer, affords the best illustration of this underground mischief. Nothing can look smoother and more even than the bottom, until that uncompromising test of accurate levels, the water, makes its appearance: all on a sudden the whole scene is changed, the eye-accredited level vanishes as if some earthquake had taken place: here, there is a gravelly scour, along which the stream rushes in a thousand little angry-looking ripples ”

“ The waters have worn down the rocky bottom to such an extent that in order to stand in full view of the splendid fall we must make for a gap in the foliage, and scramble down some natural steps in the wall of rock forming low cliffs along each side of the flood. The water comes over three terraces of solid stone, and then sweeps across wide ledges in a tempestuous sea of waves and froth, until there come other descents which alter the course of parts of the stream, so that as we look across the riotous flood we can see the waters flowing in many opposite directions. ”

“ There and then the heavens opened and the floods came and beat into that open maw of that vast crevasse and filled it full in an instant.
As the deluge came roaring down, bearing onward the sweepings and scourings of the [Pg 114] mountains, he caught a glimpse of her white desperate face rising, falling, now disappearing, now coming into view again, in the foamy midst of the torrent. He ran to the cliff bank and throwing aside his gun he scrambled down the wall to a certain shelf of the rock over which the rising water broke thinly. Ordinarily it was twenty feet above the creek bed. ”

“ Descending to the bottom, the impression is like being in a deep vault, this subterranean world disclosing operations lasting through ages, during which the rocks have slowly yielded to the resistless power of the water and frost that has gradually cut the chasm. Fossils and petrifactions found in the deepest strata are trod upon, and each thin layer of the walls, one imposed upon the other, shows the deposit of a supervening flood happening successively, yet eternity only knows how long ago. ”

“ High banks of clay and gravel, which at low-tide seem as though they were far removed from submersion, are flooded instantly, to remain so until the ebb takes place. The natives never fail to remember the angry warning of this incoming tide; they always hurriedly rush out of their huts, scan quickly everything surrounding, lest some utensil, some canoe, or basket-weir be thoughtlessly left within the remorseless rush of that swift-coming flood. ”

“ A third ravine was split through the rock, and this time the earth's crust cracked away to the eastward, giving outlet to the sea, which came pouring through the canon, breaking rocks from mountains and grinding them to powder in its terrific progress. Gasping with fatigue, the unhappy one toiled up a hill and surveyed his work with satisfaction, for the flood engulfed the fiend men and they left no member of their race behind them. ”

“ The effect of this lifting was to raise the mouths of the two rivers, and throw back their waters on the city, and this overflow added its share of mud, ashes, and vegetable matter. Nor must we omit the canals filled up, the sewers choked, the aqueducts shattered by the earthquake, and pouring their contents into the valley. By degrees, as the mud settled in the streets, the courts, rooms, and dwellings, the level of the water rose, new deposits gathered; the ashes falling in dense masses from the sky, grew saturated, and increased the rising heaps. ”

“ It is no longer the stately stream, whose mystic beauty, noble grandeur, and gentle, uninterrupted flow along a course of nearly nine hundred miles ever fascinated us, despite the savagery of its peopled shores, but a furious river, rushing down a steep bed obstructed by reefs of lava, projected barriers of rock, lines of immense boulders, winding in crooked course through deep chasms, and dropping down over terraces in a long series of falls, cataracts, and rapids. ”

“ These great sinkings, though produced by accidental causes, hold a first place in the principal circumstances in the History of the Earth, and not a little contributed to change the face of the Globe; the greatest part of them have been produced by subterraneous fires, whose [52] explosions cause earthquakes and volcanos; the force of these inflamed and confined matters in the bowels of the earth is beyond compare; by it cities have been swallowed up, provinces overturned, and mountains overthrown. ”

“ And when I went to look at them, I found that they came out of the rock just where the limestone and the granite joined. “Ah,” I said, “now I think I have Madam How’s answer. The lid of one of her great steam boilers is rather shaky and cracked just here, because the granite has broken and torn the limestone as it lifted it up; and here is the hot water out of the boiler actually oozing out of the crack; and the earthquake I heard last night was simply the steam rumbling and thumping inside, and trying to get out.” ”

“ This condition extended down the canyon for twenty miles or more. Judging by the amount of lava the eruption must have continued for a great while. Could one imagine a more wonderful sight—the turbulent stream checked by the fire flood from above! What explosions and rending of rocks there must have been when the two elements met. The river would be backed up for a hundred miles! Each would be shoved on from behind! There was no escape! They must fight it out until one or the other conquered. ”

“ I squinted seaward and saw very near at hand the tide rips tumbling in a rising gulf swell.
“There’s only one chance for him on God’s green earth,” said I. “If he goes into those rips without steerageway—good night. If the back eddy catches him, we might heave him a line as she swings past. Come on!”
Past the mouth of the lagoon, a low cliff gave straight down on the eddy’s sweep, and I had often noticed that driftwood making its interminable round passed under the cliff. At the end of my cabin hung a coil of half-inch rope. ”

“ A chilly twilight reigned in the ravine, and the noise that came up from the ruin of the torrent seemed doubly accented by reason of it. The sound of water moving in darkness has always conveyed to me an impression of something horrible and deadly, be it nothing of more moment than the drip and hollow tinkle of a gutter pipe. But the crash in this echoing gorge was appalling indeed. ”

“ The mountain heights which bound it, being composed for the most part of schist, mica slate, and talcose slate, large masses become detached in winter—split off by the freezing of the water behind them—when they descend, on the coming of thaw, in terrible avalanches of stone and mud. Sometimes the masses are such as to dam up the river and form temporary lakes, until the accumulation of force behind bursts the barrier, and a furious flood rushes down the valley. ”

“ Never did she go up the cliff but that great boulders would break loose under her ponderous tread, and tumbling headlong with mighty bound, would dash down the steep mountain-side and land with a roaring crash in the bed of the river below, where to this day they may be seen choking the tide of the stream in a great rocky mass. ”

“ Among these revolutions of nature, we never reckon common inundations, such as take place at present from water overflowing its boundaries, though these also may produce devastation whose effects remain visible for an hundred years. But, in mountainous districts, another kind of aqueous eruption makes its appearance, and may be classed along with the traditions of a deluge. We very frequently, for instance, observe the valleys of high mountains forming a range of basins separated from one another by shorter or longer defiles, and opening through the last defile into a wider valley, or a marsh. ”

“ The rain filtering down the porous layer to the bottom of the basin, forms there a subterranean pore, which, with the liquid or semi-liquid column pressing upon it, constitutes a sort of huge natural hydrostatic bellows; sometimes the pressure on the superincumbent crust is so great as to cause an upheaval or disturbance of the valley, and there can be little doubt that many earthquakes that are manifestly not of volcanic origin, are due to this simple cause.”— (Ninth edition Encyclopedia Britannica.) ”

“ But the limestone is full of holes, caves, and cracks, and the torrent rushing down and beating against the great escarpment, impatient to get through and resenting the detour, bored till at last it burst a way through, and having once penetrated proceeded to enlarge the portal, till the river even in its greatest floods can rush through. ”