The earliest earthquake recorded in the area was in 1638, in the journal of Governor John Winthrop. He wrote, “Between three and or four in the afternoon…there was a great earthquake. It came with the noise of continual thunder, or the rattling of coaches in London…the noise and shaking continued about four minutes.”
Although the U. S. Geological Survey concludes Connecticut has had relatively moderate seismic activity, we have historical accounts of a few earthquakes which destroyed property and terrified inhabitants.
The quake of July, 28 1791, centered in East Haddam, was the worst earthquake recorded in Connecticut history. The quake violently shook 2,000 square miles of land in Connecticut and Massachusetts, sending aftershocks from Boston to New York. It is estimated that the "Moodus Quake" as it was called, registered between 4 and 5 on the Richter scale.
According to accounts from Connecticut’s Disasters by Ellsworth S. Grant, the quake began at 8 p.m. and struck with a series of shocks. Chimneys collapsed, stones walls tumbled and doors were thrown open by the force. Homes collapsed and contents were tossed about. Schools of fish were spotted leaping out of the waters. The virulence was so great, the earth cracked open creating fissures, some over 100 feet in length. Close to 100 aftershocks were felt within the next 24 hours.
According to accounts by a “worthy gentleman” mentioned in Connecticut’s Historical Collections, the quake was described as “intermediate degrees between the roar of a cannon and the noise of a pistol.” The description continued,” Here, at that time, the concussion of the earth, and the roaring of the atmosphere, were most tremendous. Fear and consternation filled every house.”
The earthquake, combined with ardent theocentrism - the belief that God is at the center of existence - struck the masses with fear. Many believed it was the work of God striking out, a belief that was reflected in sermons following the quake.
An onslaught of curious visitors came to Connecticut after the disaster, to catch some rumblings. Lore of a British wizard named Dr. Steele stopped by the epi-center, claiming there was a large jewel called The Witches Carbunkle, buried beep within Mount Tom, which he claimed was the source of the violent Connecticut quakes.
Legend has it that he removed the jewel and absconded down the Connecticut River. It was reported by witnesses that Dr. Steele effectively quieted the rumblings for a while anyway.
Since then only a handful of mentionable quakes have struck over the years, but nothing with the intensity or lore of the quake of 1791.