"[Volvelle]", Galluci, Giovanni Paolo
Subject: Cartographic Miscellany
Period: 1614 (published)
Publication: Theatro del mundo ye del tiempo Granada
Color: Black & White
7 x 10 inches
17.8 x 25.4 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. It consists of two separate movable paper discs rotating on a red satin ribbon that pivots in a graduated circle engraved with the months of the year. These were included in scientific books and atlases and because of their delicate nature most have not survived intact.