Early on the morning of December 5, 1820, a spark flared at a gunpowder factory owned by Messrs. Hale, Whipple, and Tileston. The subsequent explosion consumed 2,000 pounds of gunpowder and could be heard 30 miles away. According to the History of Chelmsford, the explosion was probably caused "by the friction of the pestle against the mortar."
Four men were killed: Levi Marshall, Nathaniel Marshall, Sherburne Chase, and John Ives.
The epitaph tells the story:
to the memory of
LEVI AE 26 & NATHANIEL AE 23,
Mr. James & Mrs. Joanna Marshall,
whose deaths, together with those of
Sherburne Chase of Litchfield, N.H.
and John Ives of Sudbury
were occasioned by the explosion of
the Powder Mill in Chelmsford,
Dec. 5, 1820.
They were pleasant in their lives,
And in their deaths they were not divided.
My age's hope my youthful boast
My soul's chief blessing and my pride,
In one sad moment all were lost
When Levi and Nathaniel died.
Levi Marshall and John Ives were
instantly killed, Sherburne Chase &
Nathaniel Marshall survived, the
former 44, the latter 24 hours.
Over the next decade, the gunpowder factory exploded again and again. The History of Chelmsford recounts these incidents:
- June 5, 1821: "Between 6 and 7 in the afternnon the powder mill took fire and exploded. Three persons were killed, Fitzgerald, Howard and Farr."
- December 11, 1821: "About 4 p.m., the drying house of the powder factory took fire from the oven and exploded. Thomas Sullivan was killed. The other buildings were much injured. Windows and barn doors in the neighborhood were burst open and broken."
- December 22, 1826: "Whipple's powder mill exploded. One man was hurt."
- January 4, 1830: "There was another explosion. The building was destroyed and Mr. Robinson was mortally injured."