ARMILLARY, Armillaris, in Astronomy, an Epithet given to an artificial Sphere, composed of a Number of Metalline Circles, representative of the several Circles of the Mundane Sphere, put together in their natural Order.
See SPHERE and CIRCLE.
Armillary Spheres ease and assist the Imagination to conceive the Constitution of the Heavens, and the Motions of the heavenly Bodies. See HEAVEN, SUN, PLANET, etc.
Such is represented, Tab. Astron. Fig. 21.—where P and Q represent the Poles of the World, A D the Equator, E L the Ecliptic and Zodiac, PA G D the Meridian, or the Solstitial Colure, T the Earth, F G the Tropic of Cancer, H T the Tropic of Capricorn, M N the Arctic Circle, O V the Antarctic, N and O the Poles of the Ecliptic, and R S the Horizon.
The Word is formed of the Latin Armilla, a Bracelet:ARMILLA Membranosa, is a Name given by some Anatomists, to the annular Ligament.
See ANNULAR LIGAMENT.
