Sundial

This sundial is executed inside a hemisphere, 60 cm. in diameter, which has been hollowed out from a large block of marble. The hemisphere is in a triangular prism shape, supported along one of its two lateral edges meaning that its two bases and one of the lateral faces are vertical. The other lateral face is horizontal and the third forms a 55-degree angle with the horizon. The sphere is tangential to the horizontal face of the prism and the centre is positioned on its inclined face. In the upper part of the dial, there is a hollow where rays of sunlight can enter. When they hit the surface of the sphere, the light marks the solar time and the season of the year. This is one of the best preserved sundials from the late Roman imperial period in the world. It was discovered during Pierre Paris’ systematic excavations in the city of Baelo Claudia in 1921.