What was Johann Christian Dieterich's friend the first to hold a dedicated professorship in in Germany?
Johann Christian Dieterich: Johann Christian Dieterich (1722–1800) was the founder of the Dieterich’schen Verlagsbuchhandlung publishing house and close friend of Georg Christoph Lichtenberg. Georg Christoph Lichtenberg:  As a scientist, he was the first to hold a professorship explicitly dedicated to experimental physics in Germany.
experimental physics