Taphophobia – Fear of being Buried Alive
In the mid 1880s, until about 1910, undertakers sold Grave Alarm devices.These were elaborate rope-and-bell/pulley arrangements allowing those buried alive to summon help.The rope was placed into the hand of the (supposed) deceased, and it wound through a series of tubes to the bell outside the grave.
This patent, one of literally dozens on coffins with escape hatches and/or signaling means, may seem odd to twenty-first century eyes, but it reflects more a change in the world than latent insanity on the part of our mid- to late-eighteenth century ancestors.
One reads in many 18th century sources of the exhumed corpses with hair and nails grown long, the fingernail scratches in the coffin lid, etc., but there are few reliably documented cases of live burial. While the reports of live burials are suspect, the fear of burial alive was very real. When the Industrial Revolution was new there were no reliable methods for determining death. At the same time, new methods of putting people in comas (electricity, chemicals, industrial accidents from the new machinery and railroads, etc.) were multiplying.
The British inventor of the first signaling coffin became wealthy, but burned himself to death in order to avoid the possibility of being buried alive.
From website: http://www.bpmlegal.com/wcoffin.html