Scaphe

'bowl'; also known as a skaphe, scaphion (diminutive) or Latin: scaphium) was a sundial said to have been invented by Aristarchus of Samos (3rd century BC).

Aristarchus of Samos (/ˌærəˈstɑːrkəs/; Ἀρίσταρχος, Aristarkhos; c. 310 – c. 230 BC) was an ancient Greek astronomer and mathematician who presented the first known model that placed the Sun at the center of the known universe with the Earth revolving around it (see Solar System).

Greeks and Romans used large stone sundials based on "a partial sphere or scaphe,” the shadow of the tip of the gnomon was the time-telling index.

The problem of projecting the three-dimensional scaphe dial upon a vertical or horizontal plane was addressed by a number of distinguished nineteenth-century mathematicians, each of whom presumably solved it to his own personal satisfaction.

A Fortran program was written for the VAX computer at the University of Leicester that enabled vertical or horizontal dials to be plotted for any latitude.