I have a cute little 127mm Goerz Series III Doppel Anastigmat in barrel, and I have just bought a 480 mm version to fit on my winter project: my dormant 12x15" camera, which itself dates from the 1880s.
I have been looking for information on the Goerz company, but very little seems to be available. The Goerz subsidiary in the USA, and the lenses produced after the merger with Zeiss-Icon in the twenties are well-documented, but the history of the parent company in Berlin is hard to get any concrete data on.
I know that the Series III was patented 1892, released for sale 1893 and changed name to "Dagor" in 1904. That dates my lenses pretty well, but it would be nice to know some more about them and the company that made them, if only for personal interest. Does anyone have any pointers?