Wireless telegraphy dates as far back as Faraday in the early 19th century, when it was discovered that radio waves could be used to send telegraph messages. After James Clerk Maxwell had predicted the existence of electromagnetic waves, and had shown that their speed of propagation is identical with that of light, it required, in reality, very little to demonstrate by experiment the existence of such waves.
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“A nap, my friend, is a brief period of sleep which overtakes superannuated persons when they endeavour to entertain unwelcome visitors or to listen to scientific lectures.”
—George Bernard Shaw (18561950)