Rare doctoral thesis on optics by Johann Friedrich Krebs (1651-1721) at the University of Jena. In the present thesis he discusses the reflection of light at various angles and heights from all sorts of surfaces, from mirrors, in the human eye, etc. He based his observations on experimental science, and studied the latest literature on the subject. Authors cited to include Galileo, Christiaan Huygens, Robert Boyle, Leibnitz and Erhard Weigel. An "additamenta varia" at the end gives 59 numbered questions and declarations on various subjects, showing the author's wide interests.
Slightly browned but still in good condition. STC German, 17th century, K 759; VD17 12:157743T (6 copies); not in Honeyman; Poggendorff.