On the afternoon of October 17th, 1814, an iron hoop on a twenty-two-foot fermentation vat at a London brewery snapped. The pressure triggered a chain reaction. The back wall of the brewery collapsed. Between one hundred and twenty-eight thousand and three hundred and twenty-three thousand gallons of dark porter ale poured into the streets of St. Giles — one of the most overcrowded and desperately poor neighborhoods in the city — at the speed of a wave.

Eight people died. Five of them were mourners at an Irish wake for a two-year-old boy who had died the day before. A mother and her daughter taking tea were killed when the flood collapsed their house. A girl died in the street. An elderly woman died of the shock.

The brewery was taken to court. The court ruled it was an act of God. The brewery avoided paying any compensation to the vi ...