On January 15, 1919, a poorly-constructed tank burst open and sent a 25-foot-high wave of molasses through Boston's North End, killing 21 people and injuring 150 others.
Ever heard the saying “slower than molasses”? Turns out it’s not true. Molasses can move pretty fast — a fact Boston residents learned the hard way nearly a century ago in what was one of the strangest disasters in American history.
Just after 12:30 p.m. on Jan. 15, 1919, a Purity Distilling Company molasses storage tank exploded in the city’s North End. As many as 2.3 million gallons of the sticky liquid spilled out in a matter of seconds.
The resulting wave spread out across a two-block radius. It flattened offices and homes, and it lifted a firehouse off of its foundation. The molasses swept away vehicles and horse-drawn carriages, and it even moved with enough force to warp the girders of the Atlantic Avenue Elevated train tracks. Those who found themselves in the flood’s path were carried away, crushed, or drowned.
To make matters worse, the molasses thickened once exposed to the winter air. After the wave subsided, scores of people lay entombed beneath a substance thousands of times more viscous than water.
First responders to the scene had to wade through feet of molasses to search for survivors — and pull 21 dead bodies from the mess.
The Shocking Cause Of The Boston Molasses Flood
After the wave of molasses subsided and rescue efforts were underway, officials began trying to determine what had caused the disaster. The owners of Purity Distilling, the United States Industrial Alcohol Company (USIA), initially claimed that anarchists had blown up the molasses tank in protest. Soon, however, it was revealed that residents had been reporting leaks in the tank since its construction.
As Stephen Puleo, the author of a book about the incident called Dark Tide: The Great Boston Molasses Flood of 1919, told The Boston Globe, "It was leaking from day one. Every time it was filled, it groaned and shuddered."
Purity Distilling reportedly painted the tank dark red to disguise the leaks in response to residents' concerns. Of course, that did nothing to fix the root of the problem.
In reality, a few different factors contributed to the initial blast behind the Boston molasses disaster. Shoddy construction, lax safety testing, and years of repeated over-filling left the tank weakened.
This became dangerous when combined with molasses' natural propensity to ferment and produce ethanol. In fact, Purity Distilling counted on this happening because they sold off that ethanol, which was an essential component in munitions manufacturing and in high demand during World War I.
But more so than that ethanol, it was carbon dioxide, another fermentation byproduct, that played a pivotal role in the Boston molasses disaster, along with unseasonable weather. A few warm winter days (by Boston standards, anyway) sped up fermentation and boosted the amount of carbon dioxide in the tank. As the internal pressure grew, it pushed the already fragile tank past its breaking point.
On that fateful January day, one of the cracks gave way — and the entire tank ripped itself apart.
The Great Boston Molasses Flood And Its Sticky Aftermath
Those who witnessed the disaster firsthand spoke of the power of the giant wave of molasses that descended on Boston's North End.
According to Boston.com, the Globe reported that a man named B.E. Kingsley who worked in an office near the tank said he heard a rumble that he thought was the elevated train. When it didn't stop, however, he looked out of his window.
"Where the tank stood there was no tank," Kingsley recalled. "Instead was a mighty wall of some kind — a giant wave of molasses. And it was sweeping rapidly down upon the office, gaining momentum every second."
He continued, "A second later, it seemed, there was a crash. Doors and windows were as if they had not existed. The molasses poured in... and everything in the office, including myself and the clerks, was toppled over like nine-pins under the weight of the wave."
The incident was over nearly as quickly as it had begun, but it left a gruesome scene in its wake.
As the Boston Post reported at the time:
"There was no escape from the wave. Caught, human being and animal alike could not flee. Running in it was impossible. Snared in its flood was to be stifled. Once it smeared a head — human or animal — there was no coughing off the sticky mass. To attempt to wipe it with hands was to make it worse. Most of those who died, died from suffocation. It plugged nostrils almost air-tight."
Hundreds of injured and dying people lay trapped in the sea of molasses. Debris from the destruction of vehicles and buildings littered the streets. Part of the elevated train trestle had even collapsed. It would take hours to pull survivors from the wreckage — and months to clean up the mess.
The Rescue Efforts And Lawsuits That Followed The Boston Molasses Flood
In the hours following the disaster, crowds rushed to the scene to survey the damage and free those who were trapped in the molasses or beneath the rubble. Rescuers used hatchets and crowbars in an attempt to reach the people who were pinned by debris. Others reached into the sticky liquid to pull victims to the surface — and came back up with severed limbs.
Describing the rescue effort, a Boston Post reporter wrote:
"Here and there struggled a form — whether it was animal or human being was impossible to tell. Only an upheaval, a thrashing about in the sticky mass, showed where any life was... Horses died like so many flies on sticky fly-paper. The more they struggled, the deeper in the mess they were ensnared. Human beings — men and women — suffered likewise."
Over the next four days, Red Cross workers, police, firefighters, and U.S. Army and Navy personnel combed through the rubble. All told, the Boston molasses disaster left 21 dead and 150 injured while causing over $7 million in property damage (which would equal more than $100 million today).
A series of civil suits followed the incident. After three years of hearings, USIA paid more than $600,000 in out-of-court settlements to the victims and their families (more than $8.4 million today).
Much of the site of the Boston molasses flood now rests within Langone Park. The only sign that the bizarre disaster ever took place is a commemorative plaque at the park entrance.