"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 ...
[Read more]
the narrowest sense of the word, it consists of a flat plate (the dial) and a gnomon, which casts a shadow onto the dial. As the Sun appears to move across the sky, the shadow aligns with different hour-lines, which are marked on the dial to indicate the time of day. The style is the time-telling edge of the gnomon, though a single point or nodus may be used. The gnomon casts a broad shadow; the shadow of the style shows the time. The gnomon may be a rod, wire, or elaborately decorated metal casting. The style must be parallel to the axis of the Earth´s rotation for the sundial to be accurate throughout the year. The style´s angle from horizontal is equal to the sundial´s geographical latitude." - (en.wikipedia.org 28.03.2020)