realized they had been burying people alive... So they would
tie a string on the wrist of the corpse, lead it through the
coffin and up through the ground and tie it to a bell.
Someone would have to sit out in the graveyard all night
(the graveyard shift.) to listen for the bell; thus, someone
could be saved by the bell or was considered a dead ringer.
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I think that is where the well known "wake" came from. Family
and friends would sit around the casket (before embalming) and talk about the dear departed, waiting, just in case he/she woke up. Gave them a chance to wake up and rejoin the living.