At lunchtime, on a mild day in January 1919, Boston's Commercial Street wharf, on the edge of the densely populated North End, was bustling. Horse-drawn wagons and motor trucks made deliveries to area businesses and to the ships moored in the harbor. Employees of the Department of Public Works took a break from their jobs at the DPW stables, offices, and workshops to eat lunch outside.

Across Commercial Street from the wharf, 65-year-old Bridget Clougherty enjoyed the warm winter weather as she hung laundry from her porch. Passenger trolleys traveled back and forth on the elevated track. Looming over all this activity was a huge dark presence, a 50-foot-tall brown metal tank. It contained 2,300,000 gallons of molasses. No above-ground receptacle in Boston had ever held more.

Suddenly there was a loud rumbling sound and then a "rat-a-tat-tat" that witnesses described as sounding like a machine gun. The ground shook as if a train were passing overhead. The awful sound of tearing metal followed. The molasses tank had come apart.

For everyone in the immediate area, the world went black as a monstrous wave of molasses engulfed everything within a two-block area. The devastation was horrific: the buildings on the dock were flattened or swept off their foundations and crushed. Employees of the Public Works department, firemen at duty in a nearby station, children playing in the street, Bridget Clougherty on the porch of her house were knocked over and drowned, or crushed by the sheer force of 26,000,000 pounds of molasses.

The next day, the Boston Post carried a graphic account. "The sight that greeted the first of the rescuers on the scene is almost indescribable in words. Molasses, waist deep, covered the street and swirled and bubbled about the wreckage. 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."

Twenty-one people died, more than 150 others were injured, and property damage totaled nearly $100,000,000 in today's dollars. As Boston struggled to recover, everyone wanted to know what had caused this disaster. Why had the molasses tank burst?

The newspapers reported that the tank had exploded. The tank's owner, U.S. Industrial Alcohol, claimed that anarchists had dynamited it as an act of sabotage. The company had reaped huge profits during World War I from converting molasses into alcohol for use in the making of munitions. After the war, with Prohibition on the horizon, U.S.I.A. was pushing to supply the liquor distilleries. As an enormously rich and powerful corporation, Industrial Alcohol was a logical target for anarchists, who were opposed to all forms of government and advocated the overthrow of the capitalist system. Anarchists had indeed bombed a number of the company's facilities in New York earlier in the decade. And Boston's Italian immigrant community was, in fact, home to some of the most radical anarchists in the country. There had been 40 explosions in Boston and nearby cities in the past year alone. When one employee reported that he had received a bomb threat against the Commercial Street tank, it lent weight to the company's version of events.

However much the company promoted the sabotage theory, it was soon to be proved false. The families of those killed and injured by the blast — mostly poor Irish and Italian laborers — contended that U.S.I.A. itself was at fault and should compensate them for their loss and suffering.

The tank, they insisted, had leaked or "wept" molasses consistently since its construction in 1915. It had long been emitting strange sounds and vibrated under the immense pressure of its contents. U.S.I.A had ignored these warning signs, caulking or patching the leaks and finally painting the tank brown in an effort to conceal them.

With largely poor and powerless working people facing off against one of the nation's largest corporations, the Massachusetts Superior Court appointed Col. Hugh Ogden, a respected former military officer, to hold hearings on the matter. After five and a half years, Ogden rendered his decision. There was no evidence that the tank had been sabotaged. Instead he found a history of negligence and mismanagement on the part of U.S.I.A.

The tank's location was chosen because of its proximity to the wharf; the company showed no concern for the safety of the people who lived and worked in the densely populated neighborhood around it.

The man who oversaw construction of the tank had no technical or mechanical training; he was unable to read a blueprint or to determine specifications that would make the steel in the tank safe. No engineers or architects were consulted; nor did an architect or engineer ever inspect it.

In the company's rush to finish construction while there was still a demand for industrial molasses, the strength of the tank was not tested before it was filled. To avoid costly interruptions in the molasses distilling process, the manager ignored employees and others who warned that the tank was unsound.

The destruction of the tank was not an act of sabotage, Col. Ogden determined, but the result of structural failure. U.S.I.A. had compromised safety to maximize production and minimize costs. He ordered the company to pay $1,000,000 in compensation to the victims of the disaster.

Massachusetts and most other states responded to the verdict by passing laws to certify engineers and regulate construction. The molasses case marked the beginning of the end of an era when big business faced no government restrictions on its activities — and no consequences.