Audiphone
an invention to assist the hearing of deaf persons, in whom the The instrument, made of a thin sheet of destroyed. ebonite rubber or hard vulcanite, is about the size of a palm leaf fan, with a handle and strings attached to bend it into a curving form, and a small clamp for fixing the string at the handles. The audiphone is pressed by the deaf person using it against his upper front teeth, with the convex side outward; when so placed it communicates the vibrations caused by musical sounds or articulate speech to the organs of hearing.