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POPULAR SCIENCE MONTHLY.
razed much that before had been upright, 'hot ashes were steaming at the water's edge, and there were immense bowlders lying in a bed of ashes.' These horizontal blasts are not hard to account for and do not
require a horizontal nozzle to project them. They are simply the result of the downblast after the heavy gravel has begun to fall, acting against the upblast from the throat of the volcano, and both together