Black Treacle Tide: 100 Year Anniversary of the Great Molasses Flood – Metro US

Black Treacle Tide: 100 Year Anniversary of the Great Molasses Flood

The mid-1800’s idiom “slow as molasses in January” might be used to describe something moving at near-glacial pace, but accounts from bewildered Bostonians who survived the Great Molasses Flood 0f 1919 tell the tale of a devastating deluge of syrup surging through the streets during one of the most bizarre and iconic disasters in the Hub’s history.

A century ago, temperatures reached about 50 degrees when a poorly constructed 50-foot-tall, 90 foot in diameter cylindrical storage tank containing 2.3 million gallons of molasses exploded on Commercial Street.

A 100-yard-wide, 25-feet-tall torrent of black treacle cascaded along the cobblestone streets at an estimated 35 miles per hour, engulfing people, dogs, horses and buckling the iron girders of the elevated railroad tracks, dislodging the adjacent Engine 31 firehouse from its foundation, and daubing two city blocks in glutinous sludge.

When the tide receded, 21 people were killed and 150 were injured.

About half the victims were crushed by the wave or by debris or drowned in the streets. The other half died from injuries and infections in the following weeks.

The Scientific American described the wave as a unique body of liquid in motion:

“A wave of molasses does not behave like a wave of water. Molasses is a non-Newtonian fluid, which means that its viscosity depends on the forces applied to it, as measured by shear rate.”

Essentially, a thick substance like molasses does not want to move unless it is put into motion, much like squeezing toothpaste or extracting ketchup from the bottle. The molasses coagulated as it cooled, creating a quicksand effect for victims who thrashed and suffocated in the streets.

“Basically, you got bowled over by a tidal wave of a sticky-sweet tsunami made of a substance 1.5 times as dense and several thousand times more viscous than water,” aerospace engineer and fluid dynamics expert Nicole Sharp told NewScientist.com.

Company lawyers for the United States Industrial Alcohol Company tried to sugarcoat their lack of maintenance with a scapegoat campaign, claiming Italian anarchists bombed the tank.

“This theory was propagated by U.S. Industrial Alcohol, the company whose subsidiary, Purity Distilling Company, owned and operated the tank,” Boston College historian Kelly Lyons said.

“They had to mount a public relations offensive to protect their reputation, especially as official reports evaluating the cause of the disaster pointed definitively toward the structural weakness of the tank. In the weeks and months after the disaster, as well as several years later when the victims sued U.S.I.A. in a civil court, U.S.I.A. consistently argued that it was Italian anarchists who bombed the tank as an attack on capitalism and the military.”

Experts agree that fluid dynamics, temperature and shoddy construction were the true culprits.

Ultimately, one of the largest civil suits in Massachusetts history was filed against the United States Industrial Alcohol Company, who eventually paid $600,000 in out-of-court settlements and approx. $7,000 per victim.

For decades after the flood, locals claimed that they could smell molasses on hot summer days.

City Archaeology Program, the Boston Parks and Recreation Department, and Boston Landmarks Commission will meet on Tuesday at 10:30 am in Langone Park, 542 Commercial Street to hold a brief ceremony in recognition of the 21 lives lost during the tragedy, and share data on the Ground Penetrating Radar survey from Fiske Center for Archaeological Research which recently located the remnants of the tank.