'Earthquake alarm' definitions:

Definition of 'Earthquake alarm'

From: GCIDE
  • Earthquake \Earth"quake`\, n. A shaking, trembling, or concussion of the earth, due to subterranean causes, often accompanied by a rumbling noise. The wave of shock sometimes traverses half a hemisphere, destroying cities and many thousand lives; -- called also earthdin, earthquave, and earthshock. [1913 Webster]
  • Earthquake alarm, a bell signal constructed to operate on the theory that a few seconds before the occurrence of an earthquake the magnet temporarily loses its power. [1913 Webster]