Berlin Observatory
The Berlin Observatory (Berliner Sternwarte) is a German astronomical institution with a series of observatories and related organizations in and around the city of Berlin in Germany, starting from the 18th century. It has its origins in 1700 when Gottfried Leibniz initiated the "Brandenburg Society of Science″ ("Sozietät der Wissenschaften") which would later (1744) become the Prussian Academy of Sciences ("Preußische Akademie der Wissenschaften"). The Society had no observatory but nevertheless an astronomer, Gottfried Kirch, who observed from a private observatory in Berlin. A first small observatory was furnished in 1711, financing itself by calendrical computations.
Discovery of Neptune
The telescope, at New Berlin Observatory (1835–1913), that discovered Neptune was an achromatic refractor with an aperture of 9 Paris inches (9.6 English inches, or 24.4 cm). Made by the late Joseph Fraunhofer's firm, Merz und Mahler, it was a high-performance telescope of its era, with one of the largest achromatic doublets available and a finely made equatorial mount, with a clock drive to move the 4 m (13.4′) main tube at the same rate as Earth's rotation. Eventually the telescope was moved to the Deutsches Museum in Munich, Germany, where it can still be seen as an exhibit.