Volvelle
Encyclopedia
Slide chart
A slide chart is a hand-held device, usually of paper, cardboard, or plastic, for conducting simple calculations or looking up information.A circular slide chart is sometimes referred to as a wheel chart or Volvelle....
, a paper
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....
construction with rotating parts. It is considered an early example of a paper analog computer
Analog computer
An analog computer is a form of computer that uses the continuously-changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved...
. Volvelles have been produced to accommodate organization and calculation in many diverse subjects. Early examples of volvelles are found in the pages of astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
books. They can be traced back to "certain Arabic treatises on humoral medicine" and to the Persian astronomer, Abu Rayhan Biruni (c. 1000), who made important contributions to the development of the volvelle.
In the twentieth century, the volvelle had many diverse uses. In Reinventing the Wheel, author Jessica Helfand
Jessica Helfand
Jessica Helfand is an author, columnist and lecturer on graphic design. She is the partner of William Drenttel of Winterhouse Studios, Winterhouse Editions and Winterhouse Institute located in Falls Village, Connecticut. She is a critic in graphic design at Yale University, where she earned her...
introduces twentieth-century volvelles with this:
The rock band Led Zeppelin
Led Zeppelin
Led Zeppelin were an English rock band, active in the late 1960s and throughout the 1970s. Formed in 1968, they consisted of guitarist Jimmy Page, singer Robert Plant, bassist/keyboardist John Paul Jones, and drummer John Bonham...
employed a volvelle in the sleeve design for the album Led Zeppelin III
Led Zeppelin III
Led Zeppelin III is the third studio album by the English rock band Led Zeppelin. It was recorded between January and July 1970 and released on 5 October 1970 by Atlantic Records. Composed largely at a remote cottage in Wales known as Bron-Yr-Aur, this work represented a maturing of the band's...
(1970).
Two games from the game company Infocom
Infocom
Infocom was a software company, based in Cambridge, Massachusetts, that produced numerous works of interactive fiction. They also produced one notable business application, a relational database called Cornerstone....
included volvelles inside their package: Sorcerer (1983) and A Mind Forever Voyaging (1985). Both volvelles served to deter piracy of the games, because they contained information needed to play the game.
Venus volvelle
The most ancient example of a simple volvelle was the pentagram from HammurabiHammurabi
Hammurabi Hammurabi Hammurabi (Akkadian from Amorite ʻAmmurāpi, "the kinsman is a healer", from ʻAmmu, "paternal kinsman", and Rāpi, "healer"; (died c...
's day that has become the symbol of witchcraft. It is actually the path of Venus in 8 years and it does rotate in full circle in a span of 1199 or 1215 years. (1200×365 days or 5×243 years) But owing to Venus averaging 583.92 days, the 750 synodic orbits in 1200 years (750×584 days) has a correction of 60 days less, or 30 days less in 600 years. This is to be noted when the ancient Great Year of 600 years is said to be oriental, and the oriental calendar includes a 60-day cycle. However, the 600-year calendar (cycle) is assumed to be Jupiter by equating it with 12-year calendar.