I once wrote a song about a mining disaster in the 1840s, or so I thought, about an 11 year old who got killed in a 'run down' with a cage load of miners. I got told locally that it isn't considered a disaster until at least 10 are killed at the same time. Casualties who died later didn't count. I imagine it was a pretty big disaster for those left behind in the days where there was no compensation, no widows benefits etc. and the families lost their homes as their houses belonged to the mine owners. Long time before MT.