An avalanche.

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1830.  “Mountain slides.” An account of four of them.—Mass. Spy, Aug. 25: from the Keensville (N.Y.) Herald.

2

1886.  The fall of large rocks, mountain-slides, great explosions, whether natural or artificial, sometimes occasion genuine earthquake tremors.—A. Winchell, ‘Walks and Talks in the Geological Field,’ p. 106.

3