Ioan. Baptistae Portae neap. De refractione optices parte, libri nouem
A 1593 Neapolitan optics treatise by Giambattista della Porta, printed in Naples for a scholarly readership, with geometric diagrams of refraction and lens geometry. The pictures are line diagrams with lettered points, circles, arcs and rays drawn in plain strokes, offering a designer clean technical schematics showing light paths and construction lines.
