A sundial on Mintaka III
A sundial is a primitive device used for ascertaining the time of day.
A sundial was present on the grounds of the Griffith Observatory in 1996. (VOY: "Future's End")
In 2366, on the planet Mintaka III, the Mintakan named Oji was her village's appointed record keeper. One of her duties was to read the sundial each day, when the sun was at its zenith. (TNG: "Who Watches The Watchers")
A visual of a sundial also appears in the opening credits for I AM ERROR.