Scaphe

The Scaphe (Ancient Greek: σκάφη scaphe "bowl") was a sundial said to have been invented by Aristarchus (3rd century BC). There are no original works still in existence by Aristarchus, but the image to the right is an accurate image of what it might have looked like, only his would have been made of stone. It consisted of a hemispherical bowl which had a vertical gnomon placed inside it, with the top of the gnomon level with the edge of the bowl. Twelve gradations inscribed perpendicular to the hemisphere indicated the hour of the day. Using this measuring instrument, Eratosthenes of Cyrene (c. 220 BC) measured the length of Earth's meridian arc. The scaphe is also known as a skaphe, scaphion (diminutive) or Latin:scaphium.