GRAY, Elisha, inventor, born in Barnesville, Ohio, 2 August, 1835. He was apprenticed at an early age to a blacksmith, and afterward to a carpenter and boat-builder. On the completion of his time he entered Oberlin College, where he devoted special attention to physical science, meanwhile supporting himself by working at his trade. As a student, he constructed the pieces of apparatus used in the class-room experimentation. In October, 1867, he obtained his first patent for telegraphic apparatus, and since then has received nearly fifty more, most of which relate to the telephone. The remainder have reference to the telegraphic repeater, telegraphic switch, annunciator, and type-printing telegraph. He found when one end of a secondary coil was connected with the zinc lining of a bathtub, dry at the time, that when he held the other end of the coil in his left hand, and touched the lining of the tub with his right hand, it would glide along the side for a short distance in making contact, giving rise to a sound that had the same pitch and quality as that of the vibrating contact-breaker. This discovery led to the invention of his speaking telephone, for which he filed specifications on 14 February, 1876. Its peculiarity is that it reproduces articulate speech by varying the resistance of a battery current. In November, 1874, he filed a caveat, and in January, 1877, received a patent for a multiplex telegraph. His system is "based upon the ability to transmit a number of tones simultaneously over the same wire, and analyze them at the receiving end. So that each tone will be audible on a particular instrument which is tuned to it, but on no other." He transmitted four messages at the same time on one wire between New York and Boston in August, 1875, and a year later he succeeded in sending eight messages in the same way between New York and Philadelphia, in 1874 he visited Europe in order to perfect himself in the study of acoustics. From 1869 till 1873 he was engaged in the manufacture of telegraphic apparatus in Chicago and Cleveland, and since has held the office of electrician to the Western electric manufacturing company. He has received the degree of D. Sc., and has published " Experimental Researches in Electro-Harmonic Telegraphy and Telephony" (New York, 1878).