Construction Phonautograph

detail of phonautogram made in 1859

Édouard-léon scott de martinville, printer , bookseller trade, inspired when happened read anatomy of human ear in course of business. phonautograph constructed analog of ear canal, eardrum , ossicles. scott created several variations of device. functions of ear canal , eardrum simulated funnel-like horn or small open-ended barrel flexible membrane of parchment or other suitable material stretched on small end. pig bristle or other lightweight stylus connected membrane, indirect linkage simulated ossicles , served amplifying lever. bristle traced line through thin coating of lampblack—finely divided carbon deposited flame of oil or gas lamp—on moving surface of paper or glass. sound collected simulated ear , transmitted bristle caused line modulated in accordance passing variations in air pressure, creating graphic record of sound waves.

martinville s first patent described flat recording surface , weight-driven clockwork motor, later , more familiar form of invention, marketed rudolph koenig in 1859, recorded on sheet of lampblack-coated paper wrapped around cylinder hand-cranked. cylinder carried on coarsely threaded rod progressed along axis rotated, producing helical tracing. length of recording accommodated depended on speed of rotation, had rapid in order resolve individual waveforms of various sounds detail. if longer-term dynamics such cadences of speech being studied, cylinder rotated more , longer recording made. phonautographs included tuning fork or other means of simultaneously recording known reference frequency.

several other inventors subsequently produced modified versions of phonautograph , recorded sound-modulated line use of various implements , in various formats, either in attempts improve on scott s apparatus or adapt specific applications. in @ least 1 instance, complete return device s conceptual origins made employing preserved parts of actual human ear.