A Sundial at Buchan-Ness Boddamn Aberdeenshire,Scotland,UK. A sundial is a device that tells the time of day when there is sunlight by the apparent position of the Sun in the sky. In the narrowest sense of the word, it consists of a flat plate the dial and a gnomon, which casts a shadow onto the dial. When the earth rotates about its axis, the sun appears to “move” across the sky, causing objects to cast shadows. A sundial contains a gnomon, or a thin rod, that casts a shadow onto a platform etched with different times. ... As a result of the tilt of the earth`s axis, the visible movement of the sun changes daily. Dating to the 19th dynasty, or the 13th century B.C., the sundial was found on the floor of a workman`s hut, in the Valley of the Kings, the burial place of rulers from Egypt`s New Kingdom period around 1550 B.C. to 1070 B.C. A properly designed and installed sundial can accurately keep track of time; but it`s solar time, which can be up to 16 minutes different from clock time. ... Sundials work by tracking the sun`s shadow across a base. The pin or plate used to cast the shadow is called a gnomon pronounced NO-men.

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