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Webster 1913 Edition
Phonautograph
Pho-nau′to-graph
,Noun.
[
Phono-
+ Gr. αὐτόσ
self + -graph
.] (Physics)
An instrument by means of which a sound can be made to produce a visible trace or record of itself. It consists essentially of a resonant vessel, usually of paraboloidal form, closed at one end by a flexible membrane. A stylus attached to some point of the membrane records the movements of the latter, as it vibrates, upon a moving cylinder or plate.