Original: The National Telegraphic Review and Operators Guide in April 1857 documented the use of the number 73 in Morse code to express "love and kisses" (later reduced to the more formal "best regards").
Simplified: In April 1857, the National Telegraphic Review and Operators Guide wrote about the use of the number 73 in Morse code to mean "love and kisses" (later changed to "best regards").