THOMAS

See also:

• ALVA
• ALVA, or ALBA, FERNANDO ALVAREZ DE TOLEDO, DUKE OF, (1508-1583)

ALVA

See also:

• THOMAS ALVA EDISON (1847– )

EDISON (1847– )  , American inventor, was born on the lrth of February 1847, at Milan, Erie county, Ohio, of mixed Dutch and Scottish descent; but his parents moved to Port Huron, Michigan, when he was seven years old . At the age of twelve he became a train news-boy an the railway to Detroit, and managed to gratify his youthful interest in chemistry by performing experiments while travelling . At fifteen he became a telegraph operator, and was employed in many cities in the United States and Canada, but frequently neglected his duties in order to carry on studies and experiments in electrical science . Before he was twenty-one he had constructed an automatic repeater, by means of which a message could be transferred from one wire to another without the aid of an operator; and he had also directed his attention to the problem of duplex telegraphy, of which he later invented a successful system . In 1869 Edison came to New York city, and soon afterwards became connected with the Gold & Stock Company . He invented an improved printing telegraph for stock quotations, for which he received $40,000 . He then established a laboratory and factory in Newark, N.J., for further experiments and for the manufacture of his inventions . In 1876 he removed to Menlo Park, and later to West Orange, N . J., where he continued his experiments . Since then his name has been prominently associated with all kinds of novelties in practical electricity . Among his principal inventions are his system of duplex telegraphy, which he later developed into quadruplex and sextuplex trans-mission; his carbon telephone transmitter; the microtasimeter, for the detection of small variations in temperature; the phonograph, which records and reproduces all manner of sounds; the cinematograph, which his improvements made practicable; and his method of preparing carbon filaments for the incandescent electric lamp . In 1878 Edison was made a chevalier of the Legion of Honour by the French government .