Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Karl Eduard Zetzsche (March 11, 1830 Altenberg April 18, 1894 Dresden) was a German mathematician and physicist. He studied in Dresden and Vienna, and in 1856 entered the Austrian telegraph service. In 1858, he became teacher in the industrial high school at Chemnitz, and in 1876 professor of telegraphy in the Polytechnic Institute at Dresden. In 1880, he was appointed telegraph engineer in the Imperial Post Office at Berlin, and in 1887 retired from public service.