The following are extracts from the account of our countryman, Mr. Stewart's visit to this terrific place.
"I can compare the general aspect of the bottom of the crater, to nothing that will give a livelier image of it to your mind, than to the appearance the Otsego Lake would present, if the ice with which it is covered in winter, were suddenly broken up by a heavy storm, and as suddenly frozen again, while large slabs and blocks were still toppling, and dashing, and heaping against each other, with the motion of the waves. Just so rough and distorted was the black mass under our feet, only a hundred-fold more terrific, independently of the innumerable cracks, fissures, deep chasms and holes, from which the sulphureous vapour, steam, and smoke were exhaled, with a degree of heat that testified the near vicinity of fire.
"At an inconsiderable distance from us, was one of the largest of the conical craters, whose laborious action had so greatly impressed our minds during the night, and we hastened to a nearer examination of it. On reaching its base, we judged it to be one hundred and fifty feet high, a huge, irregularly shapen, inverted funnel of lava, covered with clefts, orifices, and tunnels, from which bodies of steam escaped, while pale flames, ashes, stones, and lava, were propelled with equal force and noise, from its ragged mouth.
"The chattering of the islanders around our cabins, and the occasional sound of voices in protracted conversation among our own number, had scarcely ceased long enough to admit of sound sleep, when the volcano again began roaring and labouring with redoubled activity. The confusion of noises was prodigiously great. These sounds were not fixed or confined to one place, but rolled from one end of the crater to the other; sometimes seeming to be immediately under us, when a sensible tremor of the ground on which we lay took place; and then again rushing to the farthest end with incalculable velocity. The whole air was filled with the tumult; and those most soundly asleep were quickly roused by it to thorough wakefulness. One of our party sprang up in his cot, exclaiming, 'We shall certainly have an eruption; such power must burst through everything;' He had barely ceased speaking, when a dense column of heavy black smoke was seen arising from the crater directly in front of us; the subterranean struggle ceased, and immediately after, flames burst from a large cone, near which we had been in the morning, and which then appeared to have been long inactive. Red-hot stones, cinders, and ashes, were also propelled to a great height with immense violence; and shortly after, the molten lava came boiling up, and flowed down the sides of the cone, and over the surrounding scoria, in two beautiful curved streams, glittering with indiscribable brilliance.
"At the same time a whole lake of fire opened in a more distant part. This could not have been less than two miles in circumference; and its action was more horribly sublime than anything I ever imagined to exist, even in the ideal vision of unearthly things. Its surface had all the agitation of an ocean; billow after billow tossed its monstrous bosom in the air, and occasionally those from different directions burst with such violence, as in the concussion to dash the fiery spray forty and fifty feet high. It was at once the most splendidly beautiful and dreadfully fearful of spectacles."
OF THE FORMATION OF NEW ISLANDS.
You must know that most of the volcanic mountains bear evident traces of having been built up of matter thrown out, in the first place, from a crack or hole in the ground, and afterwards from the crater or cup, which would thus soon be formed. At every eruption a new layer of dust, and cinders, and lava, is added, and thus a mountain is gradually produced.
In some instances, the successive layers may be seen is the crater, as is the case with Vesuvius, of the summit of which this would nearly represent the section, if we could cut it in two.
Volcanic operations can go on very nearly as well at the bottom of the sea, as upon dry land; and if you remember what I told you before, respecting the mode in which the currents of lava flow, you will not be much surprised to hear that their progress is not stopped by the water, though it may be somewhat impeded. It is certain that the streams often travel a great way at the bottom of the sea.