Old seismographs still in operation in Northern California
Felt earthquakes are frequent on the Cape Mendocino end of the northern San Andreas fault in Humboldt County, California. For this reason a Bosch-Omori seismograph was installed by Horace Winslow of the U.S Coast and Geodetic Survey in teh old city jail in Ferndale as early as 1932. In 1981 the seismograph was moved to the Ferndale Museum where it is monitored now by James Scalvini. Data from the seismograph are sent to the Survey's National Earthquake Information Service in Golden, Colorado.
Earthquake Information Bulletin (USGS)↗