Currently I am reading a book on the symbol of seshat that correlates its look and style of the look, style, and function of the vertical gnomon. It has been said that the closer one gets to truth the more applicable it is to many situations. Wiki defines a gnomon as:
The important thing here historically for Africa is this women's symbol of Seshat being correlated to the shadows cast by the vertical gnomon, which is the foundation of architecture and surveying still used today. It is always exciting to explore early history and find connections with modern technology. As the saying goes in aegypt, there is nothing new under the Sun.
A gnomon [ˈnoʊmɒn] NO-mon, from Greek γνώμων, gnōmōn, literally "one that knows or examines",[1][2] is the part of a sundial that casts the shadow.
The term has come to be used for a variety of purposes in mathematics and other fields.
Anaximander (610–546 BC) is credited with introducing this Babylonian instrument to the Greeks.[3]
Oenopides used the phrase drawn gnomon-wise to describe a line drawn perpendicular to another.[4]
Later, the term was used for an L-shaped instrument like a steel square used to draw right angles.
This shape may explain its use to describe a shape formed by cutting a smaller square from a larger one.
Euclid extended the term to the plane figure formed by removing a similar parallelogram from a corner of a larger parallelogram.
A three dimensional gnomon is commonly used in CAD and computer graphics as an aid to positioning objects in the virtual world. By convention, the X axis direction is colored red, the Y axis green and the Z axis blue.
Hero defined a gnomon as that which, added to an entity (number or shape), makes a new entity similar to the starting entity.
In this sense Theon of Smyrna used it to describe a number which added to a polygonal number produces the next one of the same type.
The most common use in this sense is an odd integer especially when seen as a figurate number between square numbers.
NASA astronauts used a gnomon as a photographic tool to indicate local vertical and to display a color chart when they were working on the Moon's surface.
The cantilever spar of this cable-stay bridge, the Sundial Bridge at Turtle Bay in Redding, California, forms the gnomon of a large garden sundial
The Chinese also used the gnomon, mentioned in the 2nd century Nine Chapters on the Mathematical Art as being used much earlier by the Duke of Zhou (11th century BC).
In the northern hemisphere, the shadow-casting edge is normally oriented so that it points north and is parallel to the rotation axis of the Earth. That is, it is inclined to the horizontal at an angle that equals the latitude of the sundial's location. At present, such a gnomon should thus point almost precisely at Polaris, as this is within a degree of the North celestial pole.
On some sundials, the gnomon is vertical. These were usually used in former times for observing the altitude of the Sun, especially when on the meridian. The style is the part of the gnomon that casts the shadow. This can change as the sun moves. For example, the upper west edge of the gnomon might be the style in the morning and the upper east edge might be the style in the afternoon.
Gazalé, Midhat J. Gnomons, from Pharaohs to Fractals, Princeton University Press, Princeton, 1999. ISBN 0-691-00514-1.
Heath, Thomas Little (1981), A History of Greek Mathematics, Dover publications, ISBN 9780486240732 (first published 1921).
Laertius, Diogenes, The Lives and Opinions of Eminent Philosophers, trans. C.D. Yonge. London: Henry G. Bohn, 1853.
The important thing here historically for Africa is this women's symbol of Seshat being correlated to the shadows cast by the vertical gnomon, which is the foundation of architecture and surveying still used today. It is always exciting to explore early history and find connections with modern technology. As the saying goes in aegypt, there is nothing new under the Sun.
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