Conrad Henfling (1648–1716 Ansbach, Germany),Leibniz und Der Briefwechsel zwischen Henfling Conrad by Rudolf von Herausgegeben Haase, Vittorio Klostermann, Frankfurt am Main, 1982, musicologist, musician, mathematician and lawyerBaierisches Musik-Lexikon by Lipowsky, Felix Joseph, Munich, 1811, page 122. was an official and privy councilor (Hofrat) at the court of the Margrave of Ansbach, Germany. He also invented a new type of keyboard for organ and harpsichord,La musique, une pratique cachée de l'arithmétique? by Patrice Bailhace, Studia Leibniztiana, Actes du colloque L'actualité de Leibniz: les deux labyrinthes, Cerisy, 1995 the design of which was extended by Paul von Janko in his 1882 patent for a keyboard layout.Janko Keyboard Piano on Piano World
In a letter dated 30 August 1706, he wrote to Gottfried Wilhelm Leibniz dealing with many issues of music theory he sets out detailed calculations for a method of musical temperament, using Euclid's algorithm in his reasoning.Musical pitch and Euclid's algorithm Leibniz had Henfling's work published as "Epistola de novo suo systemate musico" in Miscellanea berolinensia, in 1710.Grove Music Online (Oxford University Press, 2006, acc. 3/21/06) Rudolf Haase
Further reading Leibniz und Der Briefwechsel zwischen Henfling Conrad by Rudolf von Herausgegeben Haase, Vittorio Klostermann, Frankfurt am Main, 1982, , preview at Google Books La musique, une pratique cachée de l'arithmétique? by Patrice Bailhache The Hänfling/Bümler Temperament, a Trigger for Bach’s Well-Tempered Clavier?
Not music related Theses inaugurales iuridicae circa ius retorsionis iniuriarum verbalium by Conrad Henfling, Argentorati, 1678, at Google Books
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