Ever since an outburst in the year 1500, the Mountain appears to have lapsed into a remarkable condition of quietude, even of apparent extinction, for over a century and a quarter, during which period, it may be remarked, the Sicilian volcano of Etna was unusually active. Once more the summit of Vesuvius was beginning to assume the form it had borne in the days previous to the overthrow of Pompeii; the riven crater was becoming filled with dense undergrowth and even with forest trees, amidst which wild boar made their lairs and were occasionally hunted. The learned Abate Giulio Braccini, whose account of the eruption of 1631 is the most graphic and accurate we possess, explored the crater shortly before the outbreak of the volcano, but found little to suggest any idea of an approaching convulsion. He reckoned the deep depression occupying the crest of the mountain to be about five miles in circumference, and to take about a thousand paces of walking so as to reach the lowest point within its area. He remarked abundance of brushwood on its sides, and observed cattle grazing peacefully upon the open grassy patches in the midst of the over-grown space. A deep crack, however, ran from end to end of the whole crater, which allowed persons so minded to descend amidst rocks and boulders to a large plain below the surface, whereon Braccini found three pools of hot steamy water, of a saline and sulphureous taste. Such was the tranquil aspect of the Mountain as surveyed by the Abate Braccini in the first half of the seventeenth century; to men of science signs of latent energy were certainly not wanting, yet to the ignorant, careless peasants of the hill-side and the scarcely less ignorant dwellers of the towns on the seashore, the state of repose in which the Mountain had continued for four or five generations suggested no fears or suspicions. Tilling of vineyards, building of new houses, sinking of wells, went on apace as cheerfully as though an eruption were an impossibility, till certain unmistakable portents that occurred towards the close of the year 1631 roughly dissipated this spell of fancied security. Earthquakes, more or less severe, began at this time to be felt along the whole of the volcanic line stretching from Ischia to the eastern slopes of Vesuvius; the plain within the crater of the Mountain began to heave and rise in an alarming fashion, and the water in all the local wells sank mysteriously below ground. The signs of some impending disaster coming from the heights above were too strongly marked to be lightly disregarded; the idea of a volcanic convulsion, though by this time a long-distant and vague memory, became so terrifying to the dwellers on the mountain’s flanks and in Torre del Greco, Resina and the various towns that line the seaward base of the Mountain, that the majority of the people removed themselves and their property with all speed to places of safety. Nevertheless, despite the warnings given by Nature and also by men of science and the royal officials, many remained behind in their houses, and in consequence perished, to the immense number, it is surmised, of 18,000. On the morning of Wednesday, December 16th, the long threatened eruption burst forth in earnest upon an expectant world. Amidst crashes like prolonged volleys of artillery the people of Naples and the surrounding district beheld the terrible pine-tree of smoke and ashes, described centuries ago by Pliny, ascend from the south-western side of the summit of the Mountain, veiling the sky for miles around, and so charged with electricity, that many were even killed by the _ferilli_, or lightning flashes, that darted from the smoking mass. The spectacle of the ominous pine-tree was at once followed by a terrific rumbling and an ejection of lava, which after flowing down the southern flank in several streams finally reached the sea, making the waters hiss and boil at the moment of contact. Slowly but surely these relentless red-hot rivers of lava crept like serpents along the hill-side, destroying vineyard and garden, cottage and chapel, on their downward path. Resina shared the fate of its ancient forerunner Herculaneum, whilst Torre del Greco and Portici suffered severely, as we can see to-day by noting the great masses of lava flung on to the strand at various points. To add to the universal confusion of Nature, the sea, which had now become extraordinarily tempestuous, probably owing to some submarine earthquake-shock, suddenly retreated half a mile from the coast, and then as suddenly returned in a tidal wave more than a hundred feet beyond its normal limits.