English: Photo of a Dictaphone wax cylinder dictation machine, made by Columbia Graphophone Company in the 1920s. The user pressed a button on the mouthpiece, which started the cylinder turning, and spoke into it. The sound travelled down the tube and vibrated a membrane attached to a needle cutting a groove in the wax surface of the cylinder. The needle inscribes a record of the sound vibrations into the cylinder. To replay it, the mouthpiece was detached and replaced with a pair of 'stethoscope' type earphones. Each wax cylinder can hold about 1200-1500 words, and can be reused 100-120 times by erasing it with a machine that 'shaves' the surface off. Alterations: removed caption, erased noise in white areas, increased brightness.
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{{Information |Description=Photo of a Dictaphone cylinder dictation machine, made by Columbia Phonograph Co. in the 1920s |Source=Downloaded 2008-1-12 from [http://books.google.com/books?id=KeQPAAAAYAAJ&pg=PA123 Clarence Charles Smith (1922) ''The Expert