1870's Brass Miners' Ring Dial by W & L.E. Gurley

Dip (Needle) Compass, also called an Inclination Compass; Invented to measure the vertical force of the Earth's magnetism. Incredibly precise scientific instruments allow for drawing maps of equal inclination (isoclinic).

Antique Brass Miners' Ring Dial by W & L.E. Gurley, circa 1870.

Featured in Harvard University's Collection of Historical Scientific Instruments.

Diameter: 3.5 in.

Height: 1.25 in.

Weight: 15.4 oz.