Gurley Dip Needle Lake Superior Model with Case
Detailed Description
Also known as a Forrester's Compass or Miner's Compass, a dip (or dipping) needle is an instrument for measuring the intensity of the earth's magnetic field. It is used to locate buried or hidden metal. Manufactured by W. & L.E. Gurley, Troy, New York.
Object ID: USGS-000345
Sources/Usage
Public Domain.