Crystalline heavens

in the Ptolemaic system of astronomy, two transparent spheres imagined to exist between the region of the fixed stars and the primum mobile (or outer circle of the heavens, which by its motion was supposed to carry round all those within it), in order to explain certain movements of the heavenly bodies.

See also: Crystalline

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
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The boy saw the crystalline heavens undimmed by human lights.
The right stuff for NASA
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