blast. In any event, steam, smoke, rock-dust, pumice bombs, and great blobs of half-liquid rock shot skyward from the main crater, with an earth-tremor of startling but not wrecking severity—and this discharge, extending miles into the upper air, must have initiated a series of atmospheric pressure waves; and about the time the heavier dust and bombs began to fall, or just in time to meet the recurrent wave of atmospheric pressure, the discharge of steam and other gases from the minor crater occurred. Some at least of these gases were heavier than air, and formed a black cloud which rolled down the amphitheater toward St. Pierre; according to several witnesses cross-examined by Hill, it was dense and black in front, aflame in the rear; and under the shock of the recurrent air-waves above, it was driven down on St. Pierre with such velocity that roofs flew before it like chaff, the lighthouse tower was twisted and rent into debris, heavy cannon were lifted from their carriages, and a 7-ton metal monument was blown forty yards; every vessel at anchor was careened and most of them capsized, anchor-chains were broken, and an off-shore wave was driven out of the roadstead to return in a destructive debacle. Disturbed by the initial quake, the people of the city fled to the cathedral or local shrines, sought refuge in fancied strongholds, or ran aimlessly about; when caught by the black cyclone, they were thrown against walls and amidst wreckage, bruised and burned by the red-hot rocks pouring from above, and suffocated by sulphurous fumes; then, when the gas-cloud caught fire from its own lightning or from molten rock, every living thing was scorched, seared or baked according to the local conditions of the burning. Such is the picture painted by Hill from the testimony of survivors of the Roddam and the Roraima, and of the parish priest and others who looked down on the holocaust from the cliffs flanking the St. Pierre amphitheater; Russell ascribes less effect to burning gas and more to scorching rock-powder; Borchgrevink emphasizes the evidence of electro-magnetic disturbance; but all agree that the scourge of St. Pierre was fire rather than earthquake or Pompeiian burial. The tragedy was not absolutely instantaneous; yet within three to ten minutes, the thirty thousand of St. Pierre and environs—Professor Landes, the prophetic scientist, and the misguided Governor among the rest—were no more. Thousands of bodies cumbered the debris-strewn streets or lay in the shattered houses until May 20, when Pelee again thundered—and then buried the reeking wreckage beneath a fresh layer of rock-powder. The later eruptions, like the initial one, usually combined an explosion from the main crater with an immediately subsequent one from the subordinate crater; and they sent out clouds whose movements helped to interpret those of earlier date. Thus, on May 23 Hill was able to study from below a gas-cloud like that which fell on St. Pierre; and he was even able (after realizing
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POPULAR SCIENCE MONTHLY.