‘signals’ historical pictures (exact matches)

Alphabet and numerals in Morse Code
Alphabet and numerals in Morse Code
Baudot's printing telegraph
Baudot's printing telegraph
Gregory Grasshopper
Gregory Grasshopper
Submarine telegraphy
Submarine telegraphy
Morse telegraph
Morse telegraph
London and North Eastern Railway Flying Scotsman train leaving Kings Cross Station, London
London and North Eastern Railway Flying Scotsman train leaving Kings Cross Station, London
The Age of the Train
The Age of the Train
Claude Chappe's telegraph
Claude Chappe's telegraph