If I remember correctly, the reason that maroon appears on engineers' epaulettes is in memory of those engineers who frantically tried to kep the RMS Titanic afloat as long as possible. Their selfless sacrifice in remaining below and tripping circuit breakers, allowing the ship to stay illuminated as long as possible, allowed many passengers to be evacuated who would otherwise have floundered in the dark. There is,or was, a memorial at East Park, Southampton, to the engineer officers who remained at their posts on April 15th, 1912.
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