III. On musical Duodenes, or the theory of constructing instruments with fixed tones in just or practically just intonation

This paper is intended to complete and supplement three papers on Music which I have already read before the Royal Society’. It contains a more complete theory of temperament, embracing that indicated by Helmholtz2, but not worked out by him, and its application to the theory of constructing musical instruments with an intonation practically just, without change of fingering, and, if there are three or four performers, without change of mechanism. The name Duodene refers to that collection of twelve notes, suitable to the present manuals, which is made the unit of construction.