The sun compass was designed in the 1830's for work where the magnetic compass failed (work in Wisconson near the iron ore brought about the invention). They were common in arctic exploration till at least the 1980's. The fancy ones had a precision clock movement (like a mariners chronometer) so that they could be read without movement. Most had a dial that was turned to set the time from a chronometer or radio signal (you got good at listing to WWV). They worked whenever you could tell the position of the sun.

The polarizing sun compass was developed by SAS (the airlines) in the 1950's to allow navigation during twilight and can be used to some degree during cloudy weather. The polarizing compass works on the principle that light from the sun is polarized at right angles to the line toward the sun when you look directly overhead. That angle will give you a line toward the sun and with a time hack direction like a sun compass. See: http://www2.gi.alaska.edu/ScienceForum/ASF8/865.html

Respectfully,

Jerry


Edited by JerryFountain (05/03/12 05:42 PM)
Edit Reason: reference