Tetrabiblos - The Quadripartite Mathematical
Thesis - CLAUDIUS PTOLEMY

Definition:[Source Texts of Astrology]
Claudius Ptolemy's Tetrabiblos or the Quadripartite Mathematical
Thesis is the seminal text of Western Astrology.

It comes down to us in four books,
containing a total of 61 sections. The four books are each available in full
here on separate pages. Below is an hyper-linked index to the complete
work. [See also: Ptolemy's lexicon for
the zodiac signs.]