The average person may not associate earthquakes with the eastern portion of the United States, yet some of the largest seismic events have occurred east of the Rocky Mountains. In fact, the recorded history of earthquakes in the New World began shortly after the Pilgrims landed, when in 1638, a damaging earthquake rocked Plymouth Colony.

A recently released report by one of New England's foremost seismologists has shed some light on the possible epicenter and magnitude of the 1638 earthquake. He found that the French colonists on the St. Lawrence River and the English along the Massachusetts coast felt this quake with equal intensity. In order for this to happen he believes the most likely epicenter would be central New Hampshire with a magnitude of 6.5 to 7.

The first well documented, damaging earthquake to affect New Hampshire occurred the night of October 29, 1727. This earthquake, with its epicenter located off the New Hampshire and Massachusetts coast, caused damage from Boston, Massachusetts to Portland, Maine. Brick buildings "shattered" in Haverhill, Massachusetts, chimneys toppled and large quantities of sand were ejected from the ground in Newbury, Massachusetts and in Hampton, New Hampshire.

Twenty-eight years later there occurred the Cape Ann Earthquake. This earthquake, with an estimated magnitude of 6.0, caused widespread damage along coastal New England on the night of November 18, 1755. The crew of a vessel sailing 200 kilometers offshore thought they had hit a rock. They "hove-to and cast the lead," only to find plenty of water under the keel. In Boston, twelve to fifteen hundred chimneys toppled, gable ends of brick buildings broke off and fallen bricks blocked the streets. According to John Hyde, a Boston writer, damage was particularly heavy "on the low, loose ground made by encroachments on the harbor . . ."

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