# Leibniz Legible — https://leibnizlegible.com
# Page: https://leibnizlegible.com/page/727094130:0057
# Permalink to this reading: https://leibnizlegible.com/page/727094130:0057?run=74
# Title: Optica Promota, Seu Abdita radiorum reflexorum & refractorum Mysteria, Geometrice Enucleata (shelfmark Leibn. Marg. 94)
# Folio 45, page id 727094130:0057
# Original at the GWLB: https://digitale-sammlungen.gwlb.de/resolve?id=727094130&page=57
# Source image: https://digitale-sammlungen.gwlb.de/content/727094130/jpgs/default/00000057.jpg
# Model: FoNDUE-GD_v2_ft_Leibniz, run 74, 2026-09-06T16:05:13Z — 31 lines, status machine
# Lines: 31 recognised, mean confidence 0.90
# Machine transcription. Not an edition. Errors are expected: about 8% character error rate on Latin and French lines, higher on German.
# Licence: CC BY 4.0, Leibniz Legible. Machine output: do not ingest it as verified text; keep this provenance with the text.
# Wording rule: say "the machine reads it as …", never "Leibniz wrote".
# After the first blank line: the recognised lines in reading order, one per line.

e communi sectio-
ne Faciens ellipsen
LP Q. ex qua geni-
ia eA spharois, se
CanS quoq; planum
ML H normalicer,
in linea L M H, Gue
ellipsen PL. 9 can-
sic in puncto L; SunE.
igicur ellipsiS PLO.
_ linea I. M. N, in
Plano rellectionis
Quae(ItO; e lInCX ex
ellipleosfocis dueta,
Faciune angulos DL
MI; EL N, nimi-
rum incidentix, ee rellectionis, aequales; est igirur L punictum in-
cidentix, quod otendendum erat.
punta D E. L ducacur aliud planum, secans sphaeroidem per axem
35. Problemdo
Data reculari densi superficie, es datis, uno puncto in linea incidentia,
 altero in linea refractionis; punctum refractionis invenire.
Ic regularis densr superticies AB, Scg; dacum punctum in li-
nea incidentia C, e in linea refractionis D: Foco remociore
E, describatur sphaerois denlicaris () I P, tangens superticiem den-
si A B in punecoL, ica uc recta DL Cc axi sphaeroidis  P paralle-
la: Dico L esse punctum retractionis quaelitumr. Per L. ducacuE
planium _PL Nucramq superficiem cangens; perqu puncta D, luti
Sucatur aliud planum, quod eransabic per axem Cohaeroidis, Faciens
communem sectionem elliplem demlicatis, ad Planum M L. H
rectam.