This is a print on demand publication. The early recognition of Ptolemy’s major astronomical writings, the “Almagest” (or “Syntaxis”) & the later “Handy Tables,” has become a commonplace in histories of ancient astronomy. But the crucial century & a half between Ptolemy & the commentator Pappus, during which Ptolemy’s works were first circulated & gained preeminence, is for mathematical astronomy as nearly barren of documents as the three centuries between Hipparchus & Ptolemy. The fragmentary text with which this monograph is concerned casts some light on both these murky periods. Moreover, it preserves quotations from Artemidorus, a still earlier critic of Ptolemy’s innovations, & Apollinarius, a prominent astronomer from the time before Ptolemy. Illustrations.