Compass Octogonal Brass

Any object that produces a shadow is potentially a sundial. The construction of a sundial will depend on the selected projection plane: the equator, the horizon, or a vertical surface.
Quadrants with a compass, introduced in the 15th century, were the first portable sundials.

This model has Compass Rose in the upper part with a needle to determine different rhumbs. On navigation charts, the 32 rhumbs are depicted converging on one side, while the other shows the rhumb over the circle of the horizon.

Compass boxed size: 9.5 x 9.5 cm