The armillary is framed by an equinoctial and a solstitial colure brass ring with engraved calibrations and surrounded by a circular white metal flat zodiac band at the equator engraved with zodiac and monthly calibrations. The equinoctial ring is canted at 23 degrees. In the center of the structure is a vertical brass rod supporting a brass sphere representing the sun, surrounded by an orrery comprised of the 8 rotating curved brass arms, each ending with a disc indicating a planet or asteroid. In addition, the orrery has a spherical (rather than disc form) Earth — rotating on a separate horizontal geared brass arm — is painted with a simple map of the continents, and set at 23 degrees. It has a rotating moon disc attached by a brass arm. The entire armillary structure is raised on an ebonized cylindrical wood stand with turned round base.
Other than Earth, the planets and asteroids are represented by circular discs set atop rotating curved brass arms. Each disc has an engraved paper label on each side with title names and text in French, and variously with illustrations of the respective planets or asteroids, and brief information about their rotation around the sun. The discs, graduated by relative size to each other — though not in proportion to the actual planets and asteroids — are from inner to outer: Mercure [Mercury], Venus, Mars, Asteroids, Jupiter, Saturne [Saturn], Uranus, and Neptune. Earth rotates and revolves at the end of a separate horizontal arm between Venus and Mars. The disc arms and Earth apparatus revolve by turning them by hand to illustrate their movement in the solar system and the Earth rotates by three gears set within the horizontal arm on which it is set. The disc arm with the moon also revolves by turning it by hand.
Armillary spheres are astronomical demonstration devices designed to show basic principles of the solar system. They are open in form, composed of a circle of celestial and astronomical rings. Indeed, the word “armillary” is derived from the Latin word armilla meaning circle or bracelet. Armillary spheres date back to ancient Greece and were commonly produced in England, France and Europe in the 18th and 19th centuries and continued to be manufactured in the 20th century. Nonetheless, even earlier examples were made, and in different countries. For example, Ptolemaic armillary spheres were produced in Islamist countries, reaching advanced levels as early as the 10th century.
An armillary sphere with the sun at the center is known as Copernican named after the astronomer Nicolaus Copernicus (1473-1543) who formulated a model of the solar system in which the planets, including earth, revolve around the sun. An armillary sphere with Earth at the center is known as Ptolemaic, named after the 2nd century A.D. Alexandrian astronomer Ptolemy who formulated the geocentric theory of the solar system. A Copernican armillary sphere generally illustrates the revolution of planets (and asteroids) within the solar system with a central sun sphere surrounded by either concentric planetary rings or an internal orrery with discs or spheroid planets. A Ptolemaic armillary sphere generally has an earth globe surrounded by circles representing the Tropics of Cancer and of Capricorn, polar circles, a meridian and a horizon band. Notwithstanding that Ptolemaic armillary spheres have a terrestrial globe in the center rather than the sun, they were created to show modern principles of astronomy including the ecliptic plane of the earth and how that relates to the apparent path of the sun and the visibility of various constellations in the zodiac throughout the year.
The offered device is a Copernican armillary insofar as the instrument shows the sun at the center to the solar system, with the planets revolving around it. The discs representing the planetary orbits may be considered an internal orrery — an instrument that shows the proportional size and relative position of the planets, and timing of their revolution. Another related standard type of French Copernican pasteboard armillary sphere with planetary discs is similar in form, and yet a different French Copernican pasteboard armillary sphere represents the planets as concentric rotating rings, rather than an internal orrery with revolving discs.
Condition: Armillary sphere generally very good, the metal with the usual overall wear and oxidation, the wooden base with light wear and shrinkage cracks. Applied paper planetary discs and world globe professionally restored
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