De radiis visvs et lvcis in vitris perspectivis et iride tractatus (1611)
De Dominis, Marco Antonio, 1560-1624 · Venetiis : Apud Thomam Baglionum · leaf 21
patet experimentis,& tractat Vitel. 24. $ 9. Radius perdendicularis 1n actione directa eft omnium fortiflimus | reliqui vero prout magis vel minus recedunt à perpendiculari , ita magis vel minus pollent fua: directa actione. Contrarium in actione reflexa contingit , nam quó remotior eft radiusà… … pendicularis radius A. D. Vi- tel. 47. a 10. Radius quicunque ve- i | nies per edita diipitium , c E H & penetrans in aliud medium Diaphanum alterius naturz , puta denfius, fi fit perpendi- cularis ad füperficiem medij denfioris , penetrabit recta ; abfque vlla fractione. V t fi lux, feu aliud…
Optics -- Early works to 1800
Internet Archive · Fisher - University of Toronto · Public domain (published before 1931). Free to use for anything.
![An illustration from Directorivm generale vranometricvm : in quo trigonometriae logarithmicae fvndamenta, ac regulae demonstrantur, astronomicaeq[ue] supputationes ad solam ferè vulgarem additionem reducuntur : opus vtilissimum astronomis, geometris, arithmeticis, perspectiuis, architectis, praecipuè militaribus, mechanicis, geographis, nec non ipsis philosophis naturalibus (1632)](https://img.insideoutlibrary.com/img/200/ia-directorivmgener00cava-113-0.webp)