PAL

Ptolemaeus Arabus et Latinus

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Federico Commandino, In Planisphaerium Ptolemaei commentarius

Venice, Paulus Manutius Aldi, 1558 · 16r

Facsimile

Sit circulus ABCDLMNO citra datum planum, qui in eo describatur ut dictum est, et siquidem circulus dato plano aequidistet aut subcontrarie ponatur figura descripta, circulus erit quod inferius demonstrabitur; sin minus, vel erit ellipsis vel aliud quidpiam ad eius formam accedens.

Circuli autem portio descripta vel erit circuli vel ellipsis portio vel paraboles vel hyperboles vel alia figura similis. Horum autem omnium ratio patet ex antedictis.