History is filled with unusual—and unlikely—disasters, but perhaps none has ever been as strange as the one which struck Boston’s North End neighborhood on an unseasonably warm January day in 1919. At around 12:30 in the afternoon, witnesses around Keany Square described feeling the ground shake, as if an elevated train were passing nearby. This was accompanied by sounds that were described as deep growling, a thunder-like bang, and something like a machine gun being fired.
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Odd as those noises were, however, they were nothing compared to what was coming. Within minutes, the region was engulfed in a massive wave of molasses, reaching 25 feet in height at its peak and moving at 35 miles per hour. The molasses swept through the streets with enough force to tip a streetcar from its tracks and even sweep buildings off their foundations. Damaging as the unlikely flood was to property, however, its devastation to life was even more significant.
A contemporary report from the Boston Post sets the scene: “Molasses, waist deep, covered the street and swirled and bubbled about the wreckage,” it shared. Besides the usual perils that accompany any flood, living things had to contend with an additional danger. “Here and there struggled a form – whether it was animal or human being was impossible to tell,” the report continued. “Only an upheaval, a thrashing about in the sticky mass, showed where any life was.”
For those who have never had any experience with molasses themselves, the sugary substance is sticky and syrupy and thick, fully 40% more dense than water. This made it almost impossible for anything caught in the path of the molasses to struggle through it. “Horses died like so many flies on sticky fly-paper,” the Boston Post reported. “The more they struggled, the deeper in the mess they were ensnared. Human beings – men and women – suffered likewise.” While the weather that day was warm for January, around 40 degrees Fahrenheit, it was still cold for molasses, and the syrupy substance quickly began to congeal, making rescue efforts even more difficult.
In all, approximately 150 people were injured in the course of the event, and 21 people were killed. Dogs, cats, and horses weren't spared either, though no official count exists of their fatalities.
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So, what caused this peculiar disaster? There have been numerous theories advanced over the years, and we’ll probably never know for certain. But to understand a little more about it, we first have to look at the nature and uses of molasses. While we may think of molasses primarily as a food product, in 1919 it was used for a number of different things, including the production of ethanol, which was a common ingredient in both alcoholic beverages and munitions.
As such, the Purity Distilling Company had a very large tank for storing molasses that was brought into the Boston Harbor by ship. The tank stood some 50 feet tall and, at the time of the disaster, is believed to have contained around 2.3 million gallons of molasses.
The days leading up to the disaster had been typically frigid for January, but on January 15, the temperature climbed dramatically. It had been just 2 degrees the day before, and rose to 41 degrees on the day of the accident. This, combined with the addition of warmer molasses to the cooler molasses already in the tank, may have caused the expansion of the substance within, or the buildup of pressure within the tank. Other sources suggest that the tank itself had been built with lax safety standards, and had experienced problems from the moment of its construction just a few years before.
The Purity Distilling Company, meanwhile, claimed that the tank had been blown up by anarchists who opposed the use of the molasses in producing munitions. However, after three years of hearings, the company was ultimately found liable in the disaster, and paid out around $628,000 in damages and class action lawsuits, which would adjust to more than nine million in today’s dollars.
Whatever the causes, on January 15, 1919, conditions were just right for the massive tank to rupture in an explosion. The machine-gun like sound that witnesses reported hearing were actually the rivets popping loose, while the roar of the molasses escaping confinement and rushing down the streets warned others of impending danger, albeit not quickly enough for most to take cover. Indeed, the Boston Globe described people being “picked up by a rush of air and hurled many feet”, while Smithsonian magazine wrote that some people were caught in the wave of molasses itself and “carried, tumbling on its crest, almost as though [they were] surfing.”
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Army and Navy personnel, Red Cross nurses, and local police all responded to the disaster, with many rescuers working through the night, as temperatures plummeted again and the molasses became increasingly stiff. A makeshift hospital was set up in a nearby building to treat the injured, while the sticky goop made it nearly impossible to find all of the dead. It was four days before rescuers quit searching and even then, some of the victims had been swept out into the harbor and were not recovered for months.
The damage caused by the flood was considerable, but even the simple act of trying to clean up all the molasses was a laborious and time-consuming undertaking, with several hundred people working for weeks. Indeed, it is said that the water in the harbor was stained brown until summer that year. For decades after the incident, residents swore that the neighborhood smelled of molasses on hot summer days.
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It was almost impossible to get clean from the sticky goo, and rescue workers, cleanup crews, and curious onlookers managed to track molasses nearly everywhere in the city in short order. “Everything that a Bostonian touched was sticky,” Smithsonian magazine wrote in 1983, looking back on the disaster.
Today the Great Molasses Flood is mostly remembered as an odd bit of eccentric historical trivia, referenced and lampooned in songs from bands such as Lemon Demon and The Darkest of the Hillside Thickets and an episode of Comedy Central’s Drunk History. However, at the time the disaster was a most serious catastrophe, costing numerous lives and leading to a wide range of changes in laws and government regulations regarding construction and storage of large quantities of even seemingly innocuous substances—like molasses.
Sources: NPR