Wireless telegraphy came to mean Morse code transmitted by radio waves (electromagnetic waves), initially called "Hertzian waves", discovered by Heinrich Hertz in 1886. The first practical wireless telegraphy transmitters and receivers were developed by Guglielmo Marconi beginning in 1895.
BLAINE (Robert Gordon)
BLAINE (Robert Gordon) AETHERIC OR WIRELESS TELEGRAPHY [Reprint]
COLLINS (A. Frederick)
COLLINS (A. Frederick) WIRELESS TELEGRAPHY Instruction Paper.
ECCLES (W.H.) WIRELESS TELEGRAPHY AND TELEPHONY A Handbook Of Formulae, Data And Information.