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Webster 1913 Edition
Phoneidoscope
Pho-nei′do-scope
,Noun.
[
Phono-
+ Gr. εἶδοσ
form + -scope
.] (Physics)
An instrument for studying the motions of sounding bodies by optical means. It consists of a tube across the end of which is stretched a film of soap solution thin enough to give colored bands, the form and position of which are affected by sonorous vibrations.