Page:Collier's New Encyclopedia v. 10.djvu/242

LEFT VESUVIUS 204 VESUVIUS are highly important bodies. In the Protestant Episcopal Church in the United States a committee is chosen an- nually by the parish, who, in conjunction with the church wardens, manage its temporal concerns. VESUVIUS, a volcanic mountain in the Bay of Naples; supposed to have been heaved up from the submarine level where it was formed. Besides the shells which indicate its sea origin, it contains erratic blocks of limestone from the higher Apennine offshoot, Monte Som- ma, which, in an irregular semicircle, surrounds it on the N. and E. The latter was the seat of volcanic activity long before Vesuvius, which first (a. d. 63) became convulsed by earthquakes, re- peated at intervals till 79, in which year occurred its earliest known eruption. Another memorable outbreak was that of 1822, when the so-called "smoke" from the crater rose to a height of 10,000 feet, emitting flashes of lightning, raining tor- rents of hot water, and flooding the vil- lages of S. Sebastian© and Massa. In 1855 occurred a terrible eruption, in which the summit of the cone discharged a lava stream which ravaged the fertile and highly cultivated region below. On Dec. 8, 1861, Torre del Greco suffered severely from another visitation, sur- passed in turn by that of 1871-1872, when the sudden emission of lava from a crater of 1855 killed 20 spectators on the spot, S Sebastiano and Massa were again greatly damaged, the cone threw up fragments of rock to a height of 4,000 feet, and the explosions were so loud that the whole countryside fled panic MOUNT VESUVIUS This was followed by others, of which the more memorable are that in 472, when its ashes alighted in Constanti- nople; in 512, when they were wafted to Tripoli; in 1036; and in 1500; after which ensued a period of inaction, broken in December, 1631, by a destructive out- break which denuded the mountain of the forest growth with which it had be- come clothed. The 18th century wit- nessed many of its eruptions, the most remarkable being that of 1793, when a lava stream 12 to 40 feet thick swept over Torre del Greco and penetrated the^ sea to a distance of 380 feet, by which time its volume was 1,204 feet wide and 15 feet high. This stream was so liquid that to leave the crater and enter the sea — a journey of 4 miles — took only six hours. stricken to Naples. Another outbreak occurred in April, 1906, and endangered several villages with lava streams. From the observations of many years the fol- lowing characteristics of the volcanic ac- tivity of Vesuvius have been summarized by Professor Palmieri: (1) The filling up of the crater portends an imminent eruption, and its full discharge is fol- lowed by a period of repose. (2) The narrowing of the mouth of the crater by accumulated debris impedes the flow of the lava, and this impediment leads to the outburst of lateral openings which from their greater proximity to the source of heat emit the lava in a more liquid condition, whereby its flow becomes that of a continuous stream. (3) When the internal channel is blocked by solid debris, the effort of the elastic vapor to