1-157-667 - Oxford Science Archive/Heritage Images

Ader telephone system, 1881. The man on the left is making a call which passes through the operator at the exchange, centre, to the recipient on the right. French engineer Clement Ader (1841-1926) improved upon Alexander Graham Bell's telephone. In 1880 he developed the first telephone network in Paris. Ader was also a pioneer of powered flight, designing an aeroplane which made a short flight of 300 yards in 1897, 7 years before the success of the Wright Brothers.