Early Papers on the Hughes Microphone, 1878

Early appearances of David Hughes's microphone (invented in 1878), in Nature: (1) "The Microphone", pp 57-8,   May 16, 1878.  (2) AND WITH Hughes, "Hughes's Microphone", in July 11, 1878 Nature, on pp 277-8. (3) AND WITH: "On the Physical Action of the Microphone", in Nature, June 27, 1878, pp 239-240, by David Hughes. This is offered with the original wrappers.  All offered in the weekly issues, removed from a larger bound volume."Hughes's microphone, invented in 1878, was the forerunner of the various carbon microphones that were used in most telephones produced in the 20th century. From 1879 to 1886 Hughes performed a series of experiments in which his equipment transmitted wireless signals up to 500 yards."--Britannica dot com  The three issues: $95.00