Case file · Fairy lore
Tommyknockers of American mines
Cornish and Welsh immigrant miners brought the knockers to America, where 'Tommyknockers' were said to haunt the gold and silver mines of the West.
1850 CE · 39.22, -121.06 · status: legend
The account
From the 1820s the stories reached the coal country of western Pennsylvania and then the California and Nevada mining camps, where Cornish 'Cousin Jacks' were numerous; Grass Valley, California was a Cornish stronghold. Miners blamed Tommyknockers for stolen tools and snuffed candles, but also credited their knocks with warning of cave-ins. Some mine owners were asked to leave a mine open for them when it closed.
The sceptical view
Like their Cornish originals, the stories reflect the very real dangers of hard-rock mining rather than any evidence for beings underground.