On this day in 1919, hot molasses burst out of a tank at the United States Industrial Alcohol Company building and spilled into the streets of downtown Boston.
The syrupy liquid (2.5 million gallons of it to be exact!) had been stored in a 58-foot-high tank.
According to History.com, “bolts holding the bottom of the tank exploded, shooting out like bullets, and the hot molasses rushed out. An eight-foot-high wave of molasses swept away [nearby] freight cars and caved in the [United States Industrial Alcohol Company] building’s doors and windows. The few workers in the building’s cellar had no chance as the liquid poured down and overwhelmed them.”
The molasses flood killed 21 people and dozens of horses. The fiery substance even knocked over a firehouse.
You can read more about the damage and aftermath of the molasses flood here.