...Almagest

The true title of this work is Syntaxis Mathematica, which means something like ``Mathematical Treatise''. The name Almagest is probably an Arabic corruption of the work's later Greek nickname, H Megiste (Syntaxis), meaning ``The Greatest (Treatise)''.

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... inclinations,

Actually, Ptolemy erroneously allowed the inclinations of the deferents and epicycles to vary slightly.

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... orbits.

In fact, the planets revolve on small circular epicycles, whose centers revolve around the sun on eccentric circular deferents.

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... earth.

The one exception to this rule is the moon, which is sufficiently close to the earth that its parallax is significant--see Sect. 6.4.

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... plane.

In fact, $\epsilon$ is very slowly decreasing in time. The value of $\epsilon$ used in the Almagest is $23^\circ 51'$. However, the true value of $\epsilon$ in Ptolemy's day was $23^\circ 41'$.

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