The Roman sundial at the Temple of Apollo in Pompeii.

The Romans had many types of sundials. The famous architect Vitruvius, on the 9th book of the De Architectura (‘The Ten Books of Architecture’) explains the many variations along with its inventors.

Located next to the stair of the Temple of Apollo in Pompeii, this is an example of an hemicyclium sundial invented, according to Vitruvius, by Berossus the Chaldean.