J. Zahn - OCULUS ARTIFICIALIS Oculus artificialis teledioptricus sive Telescopium, ex Abditis rerum Naturalium & Artificialium principiis protractum nova methodo, eaque solida explica- tum ac comprimis e triplici fundamento Physico seu Naturali, Mathematico Dioptrico ET Mechanico, seu Practico stabilitum…. Authore R. P. F. Joanne Zahn, Carolopolitano Sacri Candidi Canonici Ordinis Praemonstratensis in Cella DEI Superiore propre Herbipolim Professo. Cum Facultate Superiorum. Herbipoli (Wurzburg), 1685 First edition Fundamentum 1 (complete) Folio (340x220cm), (2), 7, 218pp. (some misbound), text in red and black, numerous woodcut illustrations, borders, and initials; 23 plates (some full-page), folding plate inserted between p.44 and 45 in the binding (not folded). Contemporary vellum binding. Important ex-libris of Augustin Seguin (1841-1904, Engineer and Historian of Science), and Abbatia B.M. Virginis de Tonderloo (now extint) Condition very good, blue-printed stamp of title. Plates and text are clean and well impressed. Very rare and important work on optics and optical instruments. Zahn describes several optical instruments and their construction, accompanied by detailed and interesting illustrations. In this book, Zahn illustrated a small box camera fitted with a tele-lens consisting of a convex lens of longer and a concave lens of shorter focal length. This tele-lens was known to Leonard Digges over a century earlier, but this is the first time that the system was incorporated in the camera obscura. "In size and construction, Zahn's cameras and prototypes of nineteenth-century box and reflex cameras. It is really remarkable that no further development took place until the middle of the nineteenth century: in 1685 the camera was absolutely ready and waiting for photography" (Gernsheim). Garrison & Morton 263, Krivatsky 13208. The 17th century German Johann Zahn (1641-1707), canon of the Premonstratensian monastery of Oberzell near Würzburg, authored the first edition of the present work, , “Oculus artificialis teledioptricus sive Telescopium”, in 1685. The work overall contains many descriptions and diagrams, illustrations and sketches of both the camera obscura and magic lantern, along with various other lanterns, slides, projection types, peepshow boxes. In Oculus Artificialis, Zahn's comprehensive description of the magic lantern (along with twelve other different lanterns) includes some of these lanterns showing …lens covers. This was a very important evolution in the history of the camera, because it meant that the screen could be kept dark while the operator changed the slide. Zahn used the magic lantern, whose invention he credited to Athanasius Kircher, for anatomical lectures. He also illustrated a large workshop camera obscura for solar observations using the telescope and scioptric ball. Zahn also includes an illustration of a camera obscura in the shape of a goblet, based on a design described (but not illustrated) by Pierre Hérigone. Zahn also designed several portable camera obscuras, and made one that was 23 inches long. He demonstrated the use of mirrors and lenses to erect the image, enlarge and focus it.“ “Great emphasis is given not only to the construction of instruments for astronomical observations, such as the first examples of telescopes with scioptic ball, but also to more recently invented devices, such as the microscope, of which Zahn provides detailed projects, reconstructing its history and technologicaldevelopments.”