Thomas Edison taught his second wife, Mina Miller, Morse code so that they could communicate in secret by tapping each other’s hands when their families were around.
Matthews, Scott. 1144 Random, Interesting & Fun Facts You Need To Know – The Knowledge Encyclopedia To Win Trivia (Amazing World Facts Book)
Thomas Edison was the epitome of invention in his day. He was very much a “sweat of the brow” type inventor, so the graphic above is what he was all about. He started out working a telegraph for Western Union so that is where he learned to code.