Lot consisting of the ground glass for a Voigtländer metal camera and the first printed description of this type of camera dating from 1841. The ground glass holder is a lathed brass ring (diameter 10cm), one side is cut with a fine thead to attach to the cameras body, the other side is made to take the focusing-cone which holds the magnifying glass. The holder and the etched glass are in very good original condition. Along with this extremely rare camera part comes a copy of the book 'Verhandlungen des niederösterrei chischen Gewerbevereins' published in Vienna (Austria) in 1841. This publication is a collection of lectures which were hold during the monthly meetings of the trade commission of Lower Austria in 1840. Two of the numerous articles deal with the newly invented Voigtländer camera the revolutionary portrait lens by the Austrian mathematician Josef Petzval. The first bulletin by Andreas von Ettinghausen is titeld 'Bericht der Abtheilung für Chemie und Physik über den Voigtländer'schen Apparat zur Erzeugung photographischer Porträte' and is a proposal that Voigtländer should get the silver medal for his outstanding achievement, the second is a detailed description by Friedrich Voigtländer with an a printed illustration on a separated leaflet pasted into the rear book cover. The outside of the book is quite worn, but the text part and the folded leaflet are in good condition. (1841, condition B)