To Please Both the Ear and the Eye: Moses Mendelssohn, Equal Temperament and the Delian Problem

In 1761 Friedrich Wilhelm Marpurg included in Volume V of his Historisch-Kritischen Beyträgen zur Aufnahme der Musik (Part 2, pp. 95-109) an essay giving a geometrical construction for equal-tempered division of the octave. In Marpurg's introduction to the essay he states that he is not at liberty to disclose the author's name, but in 1777, the index appended to Volume VI named Moses Mendelssohn as the author. In the intervening sixteen years, many had thought it to be the work of the theoretician Johann Philipp Kirnberger, and it is possible that Marpurg wanted to set the record straight by finally giving the credit to his friend Mendelssohn. Today there is no doubt that the attribution to Mendelssohn is the correct one.