who is credited with discovering how to transmit sound without the use of wires
Wireless telegraphy 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.[7][8] 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.[9][10] 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.[11]
Phonograph The use of a flat recording surface instead of a cylindrical one was an obvious alternative which thought-experimenter Charles Cros initially favored and which practical experimenter Thomas Edison and others actually tested in the late 1870s and early 1880s. The oldest surviving example is a copper electrotype of a recording cut into a wax disc in 1881. The commercialization of sound recording technology was initially aimed at use for business correspondence and transcription into writing, in which the cylindrical form offered certain advantages, the storage of large numbers of records seemed unlikely, and the ease of producing multiple copies was not a consideration.