Unblinking Eye

Traditional darkroom photography and historical photographic processes

Gun pages

Brauswetter Patent

Brauswetter Patent Drawing.  This drawing is from Swiss patent 5030, dated 20 April 1892, issued to Otto Brauswetter and Aktiengesellschaft Eisenwerke Gaggenau.  Rights to it must have been assigned to Theodor Bergmann, because his patent of 1893 is clearly based on it.