Definition: Def. 11.14: Sphere
A sphere is the (solid) figure enclosed when, the diameter of a semicircle remaining (fixed), the semicircle is carried around, and again established at the same (position) from which it began to be moved.
Modern Formulation
(not yet contributed)
Mentioned in:
Corollaries: 1 2 3
Definitions: 4 5 6
Proofs: 7 8 9 10 11 12 13 14 15
Propositions: 16 17 18 19 20 21 22 23
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016