Fedele Fenaroli · section 5 of 26

The Way of Counting the Keys on a Harpsichord, from the Tonic to the Octave

[Counting from the tonic, the intervals are:] a just unison; a minor second, a major second; a minor third, a major third; a minor fourth, a major fourth [=augmented]; a just fifth; a minor sixth, a major sixth; a minor seventh, a major seventh, and an octave.