Petralogy: A Treatise on Rocks
White, Cochrane & Company, 1811 - Petrology
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Common terms and phrases
ancient appearance arise basalt basaltin base beautiful become beds brown calcareous called cause cement chiefly clay colour columns common compact composed considerable consists contains continued covered crater crystallisation crystals decomposed decomposition described direction discovered Dolomieu earth effect entirely eruption Etna extremely feet felspar fire flame flint fragments frequently glass grains granite greater green grey ground half hard heat height hill HYPONOME important inches iron island Italy kind known lava layers less light marble mass matter mentioned mica miles mineral mountain nature NOME observed occur origin pass pebbles pieces porphyry present produced pumice quantity quartz remains remarkable resembling rock salt sand Saussure says seems seen side siderite similar singular smoke sometimes stone substance summit supposed surface thick tion various veins volcanic whole yellow
Page 326 - I viewed with astonishment the configuration of the borders, the internal sides, the form of its immense cavern, its bottom, an aperture which appeared in it, the melted matter which boiled within, and the smoke which ascended from it. The whole of this stupendous scene was distinctly displayed before me ; and I shall now proceed to give some description of it, though it will only be possible to present the reader with a very feeble image, as the sight alone can enable him to form ideas at all adequate...
Page 148 - The earth round the place, for above two miles, has this surprising property, that by taking up two or three inches of the surface, and applying a live coal, the part which is so uncovered immediately takes fire, almost before the coal touches the earth ; the flame makes the soil hot, but does not consume it, nor affect what is near it with any degree of heat.
Page 573 - It is not long since the quarry of Carystus has ceased to yield a certain soft stone, which was wont to be drawn into a fine thread ; for I suppose some here have seen towels, net-work, and coifs woven of that thread, which could not be burnt ; but when they were soiled with using, people flung them into the fire, and took them thence white and clean, the fire only purifying them. But all this is vanished ; and there is nothing but some few fibres or hairy threads, lying up and down scatteringly...
Page 497 - ... even to the sea." On the following day he ascended an eminence above the crater, from which he obtained a still more interesting view. " The crater," he says, " is very small ; I do not think it exceeds fifty paces in diameter, having the form of a funnel terminating in a point. During all the time I observed it, the eruptions succeeded with the same regularity as during the preceding night. The approach of the eruption is not announced by any noise or dull murmur in the interior of the mountain,...
Page 323 - Etna. to pass that tract which may properly be called the cone of Etna, and which, in a right line, is about a mile or somewhat more in length. This was extremely steep, and not less rugged, from the accumulated...
Page 459 - Toward the middle of the night this vibratory motion ceased, and was succeeded by distant shocks. The fluid mass, diminished in quantity, now pressed less violently against the walls of the aperture, and no longer issued in a continual and gushing stream, but only at intervals, when the interior fermentation elevated the boiling matter above the mouth. About 4 AM the shocks began to be less numerous, and the intervals between them rendered their force and duration more perceptible. During this tremendous...
Page 514 - ... redoubled, and nothing appeared but objects of horror and confusion ; rocks of an amazing size were raised up to a great height above the water, and the sea raged and boiled to such a degree that it occasioned great consternation. The subterraneous bellowings were heard without intermission, and sometimes in less than a quarter of an hour there were six or seven eruptions from the large furnace. The noise of the repeated claps, the quantity of huge stones that flew about on every side, the houses...
Page 327 - The upper edges of the crater, to judge by the eye, are about a mile and a half in circuit, and form an oval, the longest diameter of which extends from east to west. As they are in several places broken, and crumbled away in large fragments, they appear as it were indented, and these indentations are a kind of enormous steps, formed of projecting lavas and scoriae. The internal sides of the cavern, or crater, are inclined in different angles in different places. To the west their declivity is slight...
Page 515 - The fires, which still continued to burn, and the boil- , ing of the sea, obliged them to take a great compass, and yet they felt the air about them very hot and sultry. Having encompassed the island, and surveyed it carefully from an adjacent one, they judged it to be two hundred feet above the sea, about a mile broad, and five miles in circumference ; but not being thoroughly satisfied, they resolved to attempt to land, and accordingly rowed toward that part of the island where they perceived neither...
Page 148 - ... uncovered immediately takes fire almost before the coal touches the earth ; the flame makes the soil hot, but does not consume it, nor affect what is near it with any degree of heat. If a cane, or a tube of paper, be set about two inches in the ground, confined and...