PAL

Ptolemaeus Arabus et Latinus

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Pseudo-Ptolemy, Liber de compositione universalis astrolabii

Oxford, BL, Digby 40 · 6v

Facsimile

tis memorieque commendatis, si eius longitudinem primum in tabula signare volueris, tot gradus in virgula longitudinis ab umbone versus centrum tabule numerentur quot quot] quod F antea per canones in eius longitudine inventi fuerant. Eodem quoque modo in illius latitudine, in virgula scilicet latitudinis, agendum est. In quibuscumque ergo ergo] om. F gradibus longitudinis, scilicet et latitudinis, numerus computationis computationis] compuctionis F finitus fuerit, ab illis due linee ducantur regulariter quousque una earum alteram resecet, alteram resecet] altera reservet F nam et in earum resecatione caput ipsius stelle dimittendum erit. Hec autem que dicta sunt platice diximus que etiam nunc. The rest of the page (about two thirds) is blank except for notes or pen trials and the figure O.