A slight earthquake was recorded in Plymouth, N.H., early Friday morning, but no one reported feeling it, said John Ebel, director of the Weston Observatory at Boston College, which monitors earthquakes. The quake occurred at 12:51 a.m. and had a magnitude of 1.4, said Ebel. It is not unusual, he said, for the observatory to record minor earthquakes in that area, and earthquakes usually do not cause damage unless they have a magnitude of about 5 or above. In October, a 4.0 magnitude earthquake hit Maine about 30 miles outside Portland, and tremors were felt as far as Connecticut. But there were no reports of damage or injuries.Evan Allen can be reached at email@example.com.