Development of Apparatus for the Analysis of Sound by the Sense of Touch

An apparatus is described that applies the frequency components of speech, as spoken into a microphone, to the fingers of one hand with the purpose of enabling a deaf person to comprehend speech. Frequency is indicated by position along the fingers. The sense of touch is not called upon to make any direct frequency discrimination by distinguishing vibrational sensations of different frequencies as in previous attempts of this nature [R. H. Gault, J. Franklin Institute 204, 329–358 (1927)]. The frequency analysis is done partly electrically and partly mechanically. Small tuned steel reeds are used for the final frequency analysis. These steel reeds also serve as transducers by operating directly against the fingers. The results of a short series of experiments on a deaf person are promising but the recognition of individual consonants is difficult.