Page:Popular Science Monthly Volume 1.djvu/239

Rh The volcano then rested 124 years; the second eruption taking place A. D. 203; and the third, which was much more violent, occurred 269 years later, in the year 472. On this occasion the ashes fell over nearly the whole of Europe; they were transported to Constantinople, and even to Egypt and Syria. In 1036 there occurred a violent eruption, during which lava was for the first time ejected.

The eruption of Vesuvius in 1631 was of extreme violence, and was accompanied by great currents of lava, which flowed over the villages at its base on the side of the Bay of Naples. There were at the same time thrown out immense torrents of hot water, which wrought great desolation.

The eruption of 1779 is described by Sir William Hamilton as among the grandest and most terrible of these phenomena. White sulphurous smoke like heaps of cotton rose up in piles four times as high as the mountain, and spread about it to a proportional extent. Into these clouds, stones, scoriæ, and ashes, were projected to the height of at least 2,000 feet. On subsequent days columns of fire shot forth to full three times the height of the mountain. Masses of rock of great size were projected out of the crater, one of which measured 108 feet in circumference and 17 feet in height. Ponton says the jets of lava were thrown up to a prodigious height. A portion of the ashes and stones was drifted away to some distance; but the greater proportion of these, and nearly all the lava, still red-hot and liquid, fell upon the cone, on part of Monte Somma, and into the valley between them. The whole mass which thus fell, still vividly glowing, formed a continuous fiery expanse about two and a half miles in breadth, which, with the lofty column of fire issuing from the top, presented a magnificent but very terrific spectacle. The heat, radiating from this vast glowing surface, is said to have been perceptible at a distance of six miles all around.

In June, 1794, occurred a terrible eruption, which destroyed the town of Torre del Greco. A single stream of lava was estimated by Breislak as containing more than 46,000,000 cubic feet. A vent opened near the bottom of the mountain, 2,375 feet in length and 237 feet in breadth, which became filled with lava, and on the hardening of this presented a dike in every respect similar to the ancient basaltic dikes.

The eruption of 1822 broke up the whole top of the mountain, and formed an elliptical chasm about three miles in circumference, and supposed to be 2,000 feet deep. The principal cone tumbled in, with a terrible crash, on October 22d, [sic] and the following evening there began an eruption which lasted 12 days. The internal detonations of the mountain were described as terrific, while the ashes and dust were so great as to produce at noon in the neighboring villages a darkness deeper than midnight.

The eruption of 1855 presented a most imposing spectacle. We