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# Title: Optica Promota, Seu Abdita radiorum reflexorum & refractorum Mysteria, Geometrice Enucleata (shelfmark Leibn. Marg. 94)
# Folio 7, page id 727094130:0019
# Original at the GWLB: https://digitale-sammlungen.gwlb.de/resolve?id=727094130&page=19
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# Model: FoNDUE-GD_v2_ft_Leibniz, run 74, 2026-09-06T16:05:13Z — 39 lines, status machine
# Lines: 39 recognised, mean confidence 0.93
# Machine transcription. Not an edition. Errors are expected: about 8% character error rate on Latin and French lines, higher on German.
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# After the first blank line: the recognised lines in reading order, one per line.

Ecun radii paralleli; et guoniam eisdem liveis egrediene Forma
quibus insredicur; ingreditur aurem Forma, lineis suxerficiei per-
pencicularibus, uc hactenus dictum; ergo egrediuneur racdii, sive
forma, emedio densistimo lineis perpendicularibus: Ouxeritur
igitur sectio conica cujus omnes pervendiculares ad Cur lineaM (INL.
paralleli: calis aurem est linea recta. Supponendoigitur, radios
Parallelos Gliorcunq; A, A, A, 80. in uno plano, retringi in luper
ticiemedii densiltini, de superticiem retractionis esse circulum;
racii retracti concurrene in cenerum circuli B. uni igitur ex extremis
elt lacistactum. Supponendo eriam radios quorcunq; ex puncto
Bexiltente in medio raro prodeunces, retrinsi in medio dentistimo
cujus superficios retractionis comprehendetur linen recta DP.
omnes lincae retractae evadene parallelae in medio densisimo. Si
vero hi radii paralleli in uno plano medii densissimi, concipianeur
in medii rarioris superticie D P retrinsi, (quoniam iildem lineis
egreditur Forma quibus ingreditur) concurren omnes radiiA, A, A,
8c. in punctum B; acqs ita alteri ex exeremis est latistactum. Si
vero, rem diligenter quis incueatur, videbic (propter praedictas Pa-
ciones) omnes radios, sive parallelos sire non parallelos, in super-
ficiem refractionis circulerem medii densiltimi incidences, in cir-
culi cenrrum ConCurrere. Duaeritur autem un de hoc prOVeHIAEd
Responderur; videcur hocprorenire ex eo, quod quomodocunq;
ducatur line in circulum incidens, (dummodo cum circulo in co-
dem cplano) axis ipli parallelus duci polsic; concipiendo nimi-
ruri, circulum esse elsipleos speciem, quaris illius diamecer pO-
relt dici axis; aihde videtur, axem sectiorum coniearum, esse
lineam specialem guaelicam2. Animadverienti quoque patebie,
omnesradios, in unoplano medii densutimi parallelos, non in unum
Can: U n, Ced in quodlibet punetum altignacum, exera lineam D Li, ad
Parces BConcurrere: Oueritur etiam unde hoc proveniat? Re-
spondetur; hocvidetur provenire ex eo quod, (supponens lineim.
rectam esse hyperbolam) quodlibec punctum exera iplam poltic
Tumi 10co foci; unde viderur focum esse punetum concursus
Qualicum. P duobus aucem focis, vel realibus, vel imaginariis, is
eric punctum concurlus, qui. lonsisr. Ca radiorum incidencia di-
ltac, alioguin angulus retractionis essec major recto, quod tieri non.
Pocelt. Hilce de extremis praelibaris mecium centemus: Si au-
cen eadlios proveniences e diaphonoraro in densittimum, de e dia-
FharO.