title: Non-electric aids to hearing: a short history.
abstract: The historical development of non-electric aids to hearing is traced and a classification of the different types presented. Comparative measures of their different acoustical characteristics will be shown, indicating their relative value in various types of hearing losses. Attitudes towards such devices and principles involved in their selection in the 19th Century are discussed.
mesh_terms: D000162:Acoustics; D001290:Attitude; D004739:England; D005602:France; D006310:Hearing Aids / Q000145:classification / Q000266:history*; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049690:History, Ancient; D007494:Ireland; D007558:Italy; D013557:Switzerland