Assertion: alarm clock | /r/HasAspect | one or two bells
Facets:
value: by means of a mainspring
type: MANNER
value: to move a hammer
type: PURPOSE
Source sentences:
text: Traditional mechanical alarm clocks have one or two bells that ring by means of a mainspring that powers a gear to quickly move a hammer back and forth between the two bells or between the interior sides of a single bell.