"[Volvelle]", Galluci, Giovanni Paolo
Subject: Cartographic Miscellany
Period: 1657 (published)
Publication: Theatro del Mundo ye del tiempo Granada
Color: Black & White
5.2 x 5.2 inches
13.2 x 13.2 cm
This wonderful device was used to solve problems concerning the calendar, tide tables, the rising and setting of the sun, moon, or stars, and the positions of planets. This example consists of an engraved circular calendar, inside of which is mounted a separate movable paper disc. These were included in scientific books and atlases and because of their delicate nature most have not survived in tact.