<P> US inventors William Henry Ward ( 1871 ) and Mahlon Loomis ( 1872 ) developed an electrical conduction systems based on the erroneous belief that there was an electrified atmospheric stratum accessible at low altitude . They thought atmosphere current , connected with a return path using `` Earth currents '' ' would allow for wireless telegraphy as well as supply power for the telegraph , doing away with artificial batteries . A more practical demonstration of wireless transmission via conduction came in Amos Dolbear 's 1879 magneto electric telephone that used ground conduction to transmit over a distance of a quarter of a mile . </P>
who is credited with discovering how to transmit sound without the use of wires
Amos Dolbear