The Marconi Yearbook of Wireless Telegraphy and Telephony , 1918 states, "This signal [SOS] was adopted simply on account of its easy radiation and its unmistakable character. There is no special signification in the letter themselves, and it is entirely incorrect to put full stops between them [the letters]." All the popular interpretations of "SOS," "Save or Ship," "Save Our Souls," or "Send Out Succour" are simply not valid. Stations hearing this distress call were to immediately cease handling traffic until the emergency was over and were likewise bound to answer the distress signal.
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