Circoli per formare la Sfera Armillare / Circolo per formare la Sfera Armilare

This matching set of sheets contain the pieces to construct an armillary sphere. The central terrestrial globe is in 12 segments and would have a diameter of approximately 5.5 cm if constructed. The overall armillary sphere would have a diameter of 28 cm. The various rings of the armillary sphere include the equator, the Tropic of Cancer, the Tropic of Capricorn, the zones, and the Polar and Antarctic circles.

An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic. As such, it differs from a celestial globe, which is a smooth sphere whose principal purpose is to map the constellations. It was invented separately in ancient Greece and ancient China, with later use in the Islamic world and Medieval Europe.

Uncommon work, published in the Nuovo Atlante Geografico Universale, that was commissioned to Cassini by the Calcografia Camerale, in order to replace the obsolete De Rossi's Mercurio Geografico.

Bernardino Olivieri was a cartographer and engraver at the Calcografia Camerale di Roma located in the Collegio di Propaganda Fide.

Copper engraving, fine original colour, in very good condition.