Cubical sundial, Italian, c 1560.
© Science Museum / Science & Society Picture Library
This instrument is made of wood painted in distemper with arabesques, and was formerly in the Pitti Palace in Florence, Italy. The cube has dials on five of its faces, and the time on each of these is shown by the position of the shadow of the tip of a short style, or gnomon. These faces indicate the time in three different time systems: in old Italian hours (with the day divided into 24 equal parts starting at sunset), Babylonian hours (with the 24 hours starting at sunrise), and ancient Jewish hours (with the period from sunrise to sunset divided into 12 hours, the length of which depended upon the time of year).