Polar clock


Also found in: Wikipedia.
a tube, containing a polarizing apparatus, turning on an axis parallel to that of the earth, and indicating the hour of the day on an hour circle, by being turned toward the plane of maximum polarization of the light of the sky, which is always 90° from the sun.

See also: Polar

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
His Pseudoscope; Chronoscope; Photometer; Laleidophone; cryptology and the use of cyphers; his Polar clock and a device for measuring electrical resistance, still known today as "Wheatstone's Bridge", are all way beyond my capability to explain here.