PAL

Ptolemaeus Arabus et Latinus

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Ptolemy, Almagesti (tr. Erasmus Reinhold)

Wittenberg, Johannes Lufft, 1549 · 86r

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quam rectarum in canone acciderit, facile et hoc intelligi poterit, tum ex his, tum ex supradictis, quomodo is deprehendi et emendari queat, scilicet vel ex duplo eius circumferentiae, cuius subtensam quaerimus, vel ab excessu, ad alias quascunque datas, vel ex recta subtendente circunferentiam residuam de semicirculo.

Et series canonis haec est.