The artificial ear and the disability data gap

Abstract

On the evening of Monday, 6 September 1886, Professor William Rutherford travelled from Edinburgh to Birmingham to deliver a lecture to the British Medical Association on a subject that he described as being on 'the borderland between the realm of physics and that of consciousness'. 1 He began by inviting his audience to consider the nature of sound while they listened to a vibrating pendulum and a number of differently pitched tuning forks. After this, he started on his main topic, 'The Telephone Theory of the Sense of Hearing', inspired by the invention of the telephone ten years earlier. He enthused: 'It is, indeed, one of the most wonderful inventions of recent times', and asked his audience, 'can it throw light on the sense of hearing?'. 2 Rutherford had developed a theory of frequency transmission based on the working of the telephone and he postulated that each sound stimulated a corresponding hair cell in the ear, with a correlation between the number of hair cells and the audibility of the transmission. Rutherford had reached this conclusion by taking apart and experimenting with, variously, a telephone, a frog and a rabbit. He boasted: 'I could send as many as 352 impulses per second along the nerve of a rabbit and get a note from the muscle of the pitch of 352 vibrations per second. That is a note of the pitch of F on the lowest space of the treble clef. ' 3 It might not seem that a rabbit vibrating in F has much in common with the British Post Office. Yet not long after Rutherford's experiments, that institution was also trying to discover the extent to which the telephone could throw light on the sense of hearing. Indeed, the Post Office was soon designing telephones specifically for people with hearing loss as part of their governmentmandated state monopoly. What happened, in this short space of time, to take British telephone technology from vibrating rabbits to a telephone service for