Margen
It sounds like the start of a joke, but it killed 21 people. On January 15, 1919, in Boston's North End, a fifty-foot steel tank tore open. Inside were some 2.3 million gallons of molasses meant for industrial alcohol.
The wave burst out at around 35 miles per hour and rose several meters high. It bent the pillars of the elevated railway, knocked buildings off their foundations, and trapped people and horses in a liquid so thick that struggling only pulled you deeper. Twenty-one residents died and about 150 were injured.
The tank had been leaking for years; instead of repairing it, the company had painted it brown to hide the drips. The victims joined together in one of the first class-action lawsuits against a large corporation in the United States — and won. That absurd disaster changed building regulations across the country.
The molasses took weeks to clean up; the harbor ran brown until summer. And for decades, locals swore that on hot days the neighborhood still smelled sweet.