Ziehn, Bernhard, noted German-American music theorist and teacher; b. Erfurt, Jan. 20,1845; d. Chicago, Sept. 8, 1912. He studied in Erfurt, and was a schoolteacher in Mühlhausen. In 1868 he emigrated to the U.S., and taught German, mathematics, and music theory at the German Lutheran School in Chicago (1868-71). Subsequently he became a private music teacher, and established himself as a theorist. His “enharmonic law,” built on the principle of functional equality of chords, is an original contribution to the theory of harmony.
System der Übungen für Ciavierspieler (1881); Ein Lehrgang für den ersten Ciavierunterricht (1881); Harmonieund Modulationslehre (1887; 2nd ed., 1909; completely recast and publ. in Eng. as Manual of Harmony: Theoretical and Practical, 1907); Five-and Six-Part Harmonies (1911); Canonical Studies: A New Technic in Composition (1912; in both Eng. and Ger.); Gesammelte Aufsätze zur Geschichte und Theorie der Musik (Chicago, 1927).
HJ. Moser, B. Z.: Der deutsch-amerikanische Musiktheoretiker (Bayreuth, 1950).
—Nicolas Slonimsky/Laura Kuhn/Dennis McIntire