My grandmother was recalling her life to me over the past several months,
and she told me again that her daddy was killed in the Blue Jay Mine at the age of 26, 
but elaborated that a “hanging kettle bottom” tore loose and crushed him. 

We looked up the death certificate and it indeed stated:
“killed by fall of kettle bottoms, ” and mercilessly went on to detail:
“Manner of injury: Slate Fall”
“Nature of injury: Crushed Head”

A petrified tree stump through some complex geologic and glacial maneuvering can be trapped in the roof of the mine, studded in between the layers. When the coal is mined out around the larger “root” end, it can suddenly drop through as the smooth trunk has nothing to grip. I am not sure how this looks like the bottom of a kettle, but looked up pictures of same, and that is indeed what it looks like, a rounded shape in the roof of the mine.

A young  father in 1935 was killed by the remains of a tree that may have lived millions of years ago, but that seems preferable to an actual cast iron cauldron dropping down from no-where, which is what I had envisioned.