The Tower of the Winds, also called horologion (timepiece), is an octagonal Pentelic marble clocktower on the Roman agora in Athens. The structure features a combination of sundials, a water clock and a wind vane. It was supposedly built by Andronicus of Cyrrhus around 50 BC, but according to other sources might have been constructed in the 2nd century BC before the rest of the forum.

Tower of the Winds

The Tower of the Winds, also called horologion (timepiece), is an octagonal Pentelic marble clocktower…

In the common vertical dial, the shadow-receiving plane is aligned vertically; as usual, the gnomon's style is aligned with the Earth's axis of rotation. As in the horizontal dial, the line of shadow does not move uniformly on the face; the sundial is not equiangular.

Vertical South Dial

In the common vertical dial, the shadow-receiving plane is aligned vertically; as usual, the gnomon's…

A watch with roman numerals.

Watch

A watch with roman numerals.

An illustration of a pocket watch.

Pocket Watch

An illustration of a pocket watch.

This stem winding watch is a mechanical watch which is wound automatically by the natural motion of internally rotating parts

Self Winding Watch

This stem winding watch is a mechanical watch which is wound automatically by the natural motion of…