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within itself the seeds of its own destruction, so Kirauea, irresistible on every side, has ended its career by breaking down the bounds which contained it. The south-south-western walls, of which the exterior declivity is very steep, gave way the first; but those to the north and N. N. E., supported outside by the congealed volcanic masses which had previously burst their bounds, and flowed in confusion to a distance of forty miles, have stood firm; and, like precious monuments of history, form an interesting subject for the traveller's investigation.
"The highest point of these ruins was determined by repeated observation to be 5054 feet above the level of the sea. They resemble the outer edge of a cup, to which a portion of the overflowing matter still adheres; and show that the crater, just before being emptied, was brim-full of molten lava. This vast mass of igneous matter must, however, have been the result of long accumulation: the ancient walls to which I refer, show, by layers of carbonaceous and earthy matter interposed between those of volcanic origin, that they were respectively produced at distant intervals, during which there must have been a variation in the intensity of the heat, and in the concomitant circumstances. Frequently, a layer of blocks of lava, compact, fine grained, and united, follows one of volcanic ashes and earthy substances, similar to tufa, or rather to peperino; which, in its turn, had succeeded to one of porous lava. One layer is found to affect the magnet, another not; in some cases, the porous cavities contain crystals of laminar or ligniform talc; in others, augite, olivine, and shorl are found throughout the whole length and thickness of the bed. It would even appear, judging from a specimen which I discovered in a cleft of the ancient crater, that the same mass must have been ejected, and again undergone the action of other still more powerful fires, by which its surface has been altered, so that the interior of the mass exhibits argillaceous substances, petro-silex, and crystals of hornblende; while the exterior, which formed part of the wall of the crater, has been vitrified and cracked, displaying in its crevices sulphur and muriate of ammonia.
"The interior and lower part of the emptied basin, as it now appears, offers interesting matter for investigation. Its vast platforms, often arrayed in terraces levelled by deposits of cinders and volcanic dust, solid in appearance though actually friable, are intersected by clefts, emitting hot clouds of watery vapour, which escape with considerable force, and with a sharp whistling noise like that of the valves of a steam engine. The character of these clefts appears to be uniform. The temperature of the vapour is variable: one cleft will give 156° at the depth of a foot from the opening, while another, a few paces off, will not give more than 140°.
"Even here, on these arid heights, burnt and dried up, desolate to the eye and depressing to the spirits, Nature, as if with a benevolent regard to those who come to behold her wonders, has caused a Decandria to spring up around one of these clefts to the height of three feet, so as to intercept the escaping vapours, and to help to condense them; the precious liquid, thus protected from evaporation, was found to be delicious water, offering, in a waste of thirty miles in extent, and destitute of moisture, a basin, ever full, ever fresh, ever ready to moisten the parched lips of the wanderer.
"At two hundred paces from the welcome reservoir is the sunken furnace of Kirauea, reduced from its former grandeur to eight miles of circumference, and presenting one of the sublimest scenes of nature, the interest inspired by which can only, perhaps, be rivalled by the awe which they impress.
"It is no small effort to recall the attention from the vague contemplation of that scene to the calm investigation of facts and phenomena before us.
"The point at which I computed the height above the level of the sea is on the N. N. E. of the crater: its height is 4109 feet, which is at least 950 feet below the brim of the ancient crater: and within two paces of this spot is the edge of the precipice, which falls perpendicularly 600 feet lower to the boiling surface of igneous matter.
"The descent to this level is often precipitous, and winds among a thousand openings which vomit forth hot vapours from an area thickly strewed with tabular masses of smoking lava. Like the ice in a blocked-up channel, these tabular masses remain either standing 'on end, or heaped in horizontal or half-raised beds, and gaping with fissures over fearful cavities, resounding with noises similar to those of a roaring stormy sea.
"Six of these cavities were in violent agitation while I was exploring the crater: the height of the banks which bounded them varied; four were not more than three or four feet high; the fifth, forty feet; the sixth, 150. The extent of their surface differed no less; the first five hardly contained 12,000 square feet each, while the sixth contained nearly a million. The surface of the fiery matter in all the six reservoirs kept at the same height,—rose, sank, and was agitated simultaneously; which seems to show that it belonged to one mass of liquid lava, filling the whole area of the interior of the crater, and that the cavities, or reservoirs, as I have called them, are mere openings, and the heaps of broken lava, which block part of the crater, a mere temporary covering, or bridges, as it were, over the formidable mass below.
"No pen or pencil could adequately describe the stupendous grandeur of that ceaseless impetuosity and fury of the incandescent matter which is produced in these reservoirs by the violence and the intensity of heat; or of those fierce and glowing waves which, continuing to beat and splash against the walls of the reservoirs, produce a floating froth spun out by currents of air, in a form of capillary glass, similar to that of a floating gossamer.*
"The examination of these reservoirs is beset with danger: besides the suffocating fumes of sulphuric acid gas, the inhalation of which may prove fatal, there is a risk of falling into the fiery matter, which is every where below the superficial crust. Seldom does it confine itself to the reservoirs; often appearing unexpectedly through the cracks of the black and rugged lava over which the path lies, assuming the same outward appearance by rapid congelation, and moving almost imperceptibly in slow convolutions, twisted like a thick fluid when compressed by a porous covering. The danger is much increased by the character of the lava which this volcano produces. Information received from Sir George Mackenzie, the well-known explorer of Hecla, leads me to believe that this lava of Kirauea is a species of that kind known under the name of "cavernous," which by the intensity of its heat, and the abundance of its elastic gases, produces here, as in Iceland, tumefactions, varying from the thickness and delicacy of a soap-bubble to the size of caverns twenty or thirty feet wide. These caverns, which extend in every direction, form beneath the surface of the island subterranean channels, through which the overflowing lava makes its way; and are often covered by a hollow arch, which yields at once to the tread; so that I had frequently the misfortune of falling into them, in spite of all my precautions. Their interior furnishes for examination the most interesting incrustations of sublimed minerals, with crystalline forms, the perfection of which can hardly be appreciated without a microscope, and so delicate as scarcely to bear a breath.*
* Even in the breasts of the natives the magical influence of this spot has not been unfelt; they approach it with a sacred awe, and offer their religious adoration. And this is natural. In the contemplation of the disasters which the eruptions of the lava have spread over the plains, and of the calamities which have consequently overtaken the inhabitants, man, in his primitive state, can only see his littleness, his nothingness,—he can only feel the presence of an invincible and angry power, whom he must appease and render propitious. The divinity called Vel("; supposed to reign as the Neptune of these fiery floods, receives their adoration, and has her priestesses and her sacrifices; nor can any ceremony of antiquity have been more striking than that of the Sandwich Islanders in their sacrifice of men and swine to the burning gulph. To the largest of the six reservoirs, called Hau-mau-mau, by the natives, the terrified people make their way with prayers and offerings: into its gulf also they consign the bones of high priests, distinguished chiefs, and of those who have deserved well of their country.
"On the western flank of the crater above described, the appearances render it probable that the former surface of the incandescent matter was 300 feet higher up than it is at present; and that the opening of the crater of Mouna Roa, which is now 8000 feet above, diverted the course of the intense subterranean heat from the crater of Kirauea, or at least lowered its intensity. A probability further exists, that the incandescent matter of the interior of the crater became refrigerated and solidified in the mighty cauldron; and that after a lapse of time the base on which it stood gave way, under the renewed agency of subterranean heat, when the mass cracked and slipped. It seems also that a large mass of the solidified lava must have fallen again into the abyss, to be there re
* On tbe southern plane of the crater are deposited mounds of sulphur, more extensive than those of Solfaterra, in which the following mineral substances are found crystallised:—two varieties of the sulphnret of arsenic; the petro-alumine of tolfa and sulphate of alumine; and the ten secondary forms of the primitive octahedron of sulphur.