On January 15, 1919, the north end of Boston was enjoying an unseasonably warm afternoon, with temperatures rising into the forties. Down on Commercial Street, a massive steel storage tank towered fifty feet in the air, holding over 2.3 million gallons of thick, fermenting industrial molasses.
Built cheaply by the Purity Distilling Company, the tank had leaked from the day it was constructed. It groaned and hissed so often that neighborhood children routinely scraped oozing sweet syrup off the outer rivets with breadsticks. Whenever inspectors questioned the structural integrity, the company simply painted the steel exterior brown so the leaking syrup blended in.
At 12:30 PM, the tank finally gave up.
With a concussive roar that witnesses described as sounding like a passing elevated train or artillery fire, the bottom rivets sheared off like machine-gun rounds. The tank ruptured open, releasing a twenty-five-foot-tall tidal wave of dark, syrupy molasses rushing through the streets at thirty-five miles per hour.
The force of the wave smashed a firehouse flat, snapped steel girders supporting the Boston Elevated Railway, and picked up heavy freight wagons like matchsticks.
People caught in the open tried to outrun it, but molasses is twice as dense as water. As the viscous liquid hit the freezing winter air, it cooled and rapidly thickened into a suffocating, gelatinous quicksand.
Victims were knocked off their feet and dragged underneath the dark torrent, struggling in syrup waist-deep and chest-deep. Rescuers rushed into the streets with ropes and ladders, but horses and rescue dogs became hopelessly glued to the cobblestones alongside survivors.
The disaster killed twenty-one people and injured over one hundred and fifty.
It took weeks of salt-water hoses, broom brigades, and heavy scraping to clear the harbor district, and for decades afterward, locals claimed the entire neighborhood still smelled like sweet, warm syrup on humid summer afternoons.
Refusing to fix a massive steel vat, painting it brown to hide the leaks, and unleashing a twenty-five-foot tidal wave of suffocating pancake syrup through downtown Boston sounds like a cartoon disaster, yet it brought an entire American city to its knees. That wraps up Day 26 of Crazy History Facts!
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