Safety coffins — patented designs that would allow a prematurely buried person to signal for help — were developed by multiple inventors.

Some designs included bells connected by string to the corpse’s hands, so that any movement of the hand would ring the bell above ground.

Others included air tubes to provide oxygen while signaling systems were used.

Some were equipped with flags or speaking tubes.

The number of patents filed for safety coffin designs in the nineteenth century is a precise index of how seriously the fear of premature burial was taken by a segment of the population with both technical imagination and disposable income.

The medical profession addressed the problem from the other direction, developing more rigorous standards for the verification of death.