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On 15 January 1919 a giant tank of molasses burst on Boston's waterfront and sent a brown wave through the North End. The Short follows Rosa, a fictional grocer, and her son Enzo through the last mild morning. This is the history behind it.
A grocer and Italian immigrant. She stands in for the people of the North End whose names we'll never know.
Enzo
Her son, about nine. He fills his cup at the leaking tank.
Real Documented
A tank that leaked from the day it was finished in 1915, and often rumbled.12
Painting the tank brown to hide the leaks instead of repairing them.37
Neighbourhood children collecting the leaking molasses in pails.34
A sudden warm day: from about 2 °F to above 40 °F.7
A ship refilling the tank the day before it burst.7
The day, hour by hour
1915 to 1918
A tank that leaks from the start
The tank on Commercial Street was finished in 1915. It leaked from the start and often gave off rumbling noises.12 Rather than repair it, the owners had it painted brown so the leaks would not show. Accounts date the paint to 1918.37
The big tank on Commercial Street has leaked since the day it was built.
15 January · morning
A mild winter's day
The temperature climbed from about 2 °F to above 40 °F.7 A ship had delivered fresh molasses the day before, and the tank was nearly full.7 Children from the neighbourhood collected leaking molasses in pails.34
ENZO
Mama, look! I filled my cup at the tank again.
About 12:30 pm
The tank bursts
Witnesses heard rivets popping like machine-gun fire and a roar like a train.7 The tank split open and about 2.3 million gallons of molasses poured out.1
BOSTON15 JAN 1919 12:30
Minutes later
A brown wave
The wave was estimated at 15 to 40 feet high and moved at about 35 miles an hour.17
ENZO
Mama... the whole street is turning brown!
That day
The dead
21 people were killed and about 150 injured. Twelve horses died too.1
The weeks after
The cleanup
More than 300 people worked for weeks, using salt water from a fireboat and sand. The harbor stayed brown until summer.57
The tank leaked from the day it was built in 1915.
The company's fix: paint it brown, so the leaks don't show.
Rosa is fictional. The brown paint is real.
Every line, checked
Each line from the Short that makes a historical claim, beside what the record says.
On screen · opening
The big tank on Commercial Street has leaked since the day it was built.
The record
The tank was finished in 1915 and leaked from the start.12
High
On screen · life
ROSA
Forty degrees in January! Feels like spring.
The record
On 15 January the temperature rose from about 2 °F to above 40 °F.7
High
On screen · life
ENZO
Mama, look! I filled my cup at the tank again.
The record
North End children collected leaking molasses, usually in pails.34 Enzo is fictional; the habit is real.
A wave of molasses, two stories high, at 35 miles an hour.
The record
Estimates of the wave's height range from 15 to 40 feet, and "two stories" sits inside that range. The speed of about 35 mph is an estimate.17
Medium
On screen · aftermath
The cleanup took weeks. The harbor stayed brown until summer.
The record
The cleanup took weeks, and the harbor stayed brown until summer.57
High
On screen · fact card
The company's fix: paint it brown, so the leaks don't show.
The record
Accounts say the owners painted the tank brown instead of repairing the leaks.37 One minor account gives a different reason for the paint.
High
Why it still matters
Why it still matters
Who was to blame?
In 1925, after years in court, a judge found the tank's owner, US Industrial Alcohol, responsible.68
Historians credit the disaster with Boston's rule that engineers must sign and seal building plans before a permit is issued.68 How far the idea spread beyond Boston is less well documented.
Think about it
The leaks were visible for years. Why might people stop seeing a danger they pass every day?
Painting the tank hid the problem instead of fixing it. Who do you think should have been checking the tank, and why didn't they?
Boston changed its building rules after the flood. Can you think of other safety rules that exist because of a disaster?
Why might the wave's height and speed be given as a range rather than one number?
Glossary
Molasses
Thick, dark syrup left over from refining sugar.
Rivet
A metal pin that fastens steel plates together. The tank was built from riveted plates.
North End
Boston's oldest neighbourhood, by the harbor, home to many Italian immigrants in 1919.
Fireboat
A boat with pumps and hoses for fighting fires from the water.
Elevated railway
A railway carried on iron supports above the street; Bostonians called it the el.
Rosa
Enzo
BOSTON15 JAN 1919 12:30
ENZO
