Replica of reflectors and spark gap. In 1894 Italian scientist Guglielmo Marconi (1874-1937) began experimenting with electromagnetic waves in an attempt to find a way of sending a mesage without using wires or cables. He concentrated the waves using a curved reflector, imitating earlier experiments by Heinrich Hertz (1857-1894). In 1894 Marconi sent a signal which sounded a buzzer 9 metres away from where he stood. The following year, using these beam transmitters he succeeded in sending signals more than three kilometres (two miles), effectively the first succesful demonstration of radio telegraphy. Marconi went on to succesfully send mesages acros the English Channel in 1898, and the Atlantic in 1901.
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