WWII Cole pattern MK II sun compass, circa 1940.

8 inch dial, the reverse side of the dial has a holder for the Gnomon rods, and a spare shadow pointer.

The dial is marked for Latitudes 40° N – 40° S. With instructions for use:

TO FIND LOCAL TIME In hours & Minutes (divide longitude in degrees) by 15 & add to Greenwich Mean Time for East & subtract for West longitude.

AT NIGHT Insert 2^nd Gnomon at 180° and line the two Gnomons on Polaris. Transfer 2nd Gnomon to hole in setting arm then drive towards suitable star on required bearing.

Equation of time (added to or subtracted from mean time converts to true or apparent time)

The left-hand side of the pointer is marked: SHADOW POINTER FOR N & S LAT.

The right-hand side of the pointer is marked: INDICATOR FOR S. LAT. ONLY

Dial is on the original vehicle fixing with angle adjustment, with a later wood display base.

Height: 24 cm. Width: 22 cm.

For similar Cole MK II pattern sun compass dials see the collection of:

National Maritime Museum, object ID: ACO1415

The Cole pattern sun compass is a specialised navigation device designed by J. H. Cole during World War II. It was used by British military on armoured vehicles in the North African desert, where iron vehicles rendered magnetic compasses unreliable, instead of using Earth’s magnetic field, the Cole solar compass uses the position of the sun to determine true North. The Cole pattern sun compass was used by the Long Range Desert Group (LRDG) and the SAS.