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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. Unlike other hand-held mechanical calculating devices such as slide rules and addiators, which have been replaced by electronic calculators and computer software, wheel charts and slide charts have survived to the present time. There are a number of companies who design and manufacture these devices. Unlike the general-purpose mechanical calculators, slide charts are usually devoted to carrying out a particular specialized calculation, or displaying information on a single product or a particular process. For example, the "CurveEasy" wheel chart displays information related to spherical geometry calculations, and the Prestolog calculator is used for cost/profit calculations. Another example of a wheel chart is the planisphere, which shows the location of stars in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volvelle
A volvelle or wheel chart is a type of slide chart, a paper construction with rotating parts. It is considered an early example of a paper analog computer. Volvelles have been produced to accommodate organization and calculation in many diverse subjects. Early examples of volvelles are found in the pages of astronomy 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 introduces twentieth-century volvelles with this: The rock band Led Zeppelin employed a volvelle in the sleeve design for the album ''Led Zeppelin III'' (1970). Two games from the game company Infocom included volvelles inside their package as "feelies": '' Sorcerer'' (1983) and ''A Mind Forever Voyaging'' (1985). Both volvelles served to im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slide Rules
The slide rule is a mechanical analog computer which is used primarily for multiplication and division, and for functions such as exponents, roots, logarithms, and trigonometry. It is not typically designed for addition or subtraction, which is usually performed using other methods. Maximum accuracy for standard linear slide rules is about three decimal significant digits, while scientific notation is used to keep track of the order of magnitude of results. Slide rules exist in a diverse range of styles and generally appear in a linear, circular or cylindrical form, with slide rule scales inscribed with standardized graduated markings. Slide rules manufactured for specialized fields such as aviation or finance typically feature additional scales that aid in specialized calculations particular to those fields. The slide rule is closely related to nomograms used for application-specific computations. Though similar in name and appearance to a standard ruler, the slide rule is not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addiator
The Addiator is a mechanical add/subtract calculator, once made by Addiator Gesellschaft, Berlin. Variants of it were manufactured from 1920 until 1982. It is composed of sheet-metal sliders inside a metal envelope, manipulated by a stylus, with an innovative carry mechanism, doing ''subtract ten, carry one'' with a simple stylus movement. Some types of Addiators can also handle negative numbers (with a complementary bottom window or by providing a subtraction mode on the back side of the device). Only made obsolete by the electronic variety, it was simple and cheap for the time. It also handles non-decimal measurements, like feet and inches, or pre-decimalization pounds, shillings, and pence. Addition and subtraction require different "screens", handled by turning the instrument over, or flipping a front panel, or, later, by extended sliders and an extra lower panel. Although not always advertised (e.g. the Magic Brain Calculator mentions "add, subtract, multiply" on its fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planisphere
In astronomy, a planisphere () is a star chart analog computing instrument in the form of two adjustable disks that rotate on a common pivot. It can be adjusted to display the visible stars for any time and date. It is an instrument to assist in learning how to recognize stars and constellations. The astrolabe, an instrument that has its origins in Hellenistic astronomy, is a predecessor of the modern planisphere. The term ''planisphere'' contrasts with ''armillary sphere'', where the celestial sphere is represented by a three-dimensional framework of rings. Description A planisphere consists of a circular star chart attached at its center to an opaque circular overlay that has a clear elliptical window or hole so that only a portion of the sky map will be visible in the window or hole area at any given time. The chart and overlay are mounted so that they are free to rotate about a common axis. The star chart contains the brightest stars, constellations and (possibly) deep- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jessica Helfand
Jessica Helfand (born 1960 in Philadelphia, Pennsylvania) is a designer, author, and educator. She is a former contributing editor and columnist for Print, Eye and Communications Arts magazine, and founding editor of the website Design Observer. She is Senior Critic at Yale School of Art since 1994, a lecturer in Yale College, and Artist-in-Residence at Yale’s Institute for Network Science. Named the first Henry Wolf Resident in design at the American Academy in Rome in 2010, she is a member of the ''Alliance Graphique Internationale'' and the Art Director’s Hall of Fame. In 2013, she won the AIGA medal. Education and career Jessica Helfand is a 1978 high school graduate of George School in Newtown, Pennsylvania. She received both her BA in 1982 in Graphic Design and Architectural Theory and her MFA in 1989 in Graphic Design from Yale University. Following her graduation in 1982, she briefly wrote soap operas for Procter & Gamble, and eventually became junior scriptwriter on C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
