Hughes
We may also examine the table of the twelve tones gained through seven octaves: the sharp or flat is written to each note, excepting in the keys as they unite in succession. Each key-note by fifths is seen to become a root of the fifth higher key-note: thus A becomes the root of E, and so on. In descending, each root of the fifth lower seven becomes the fifth higher key-note; the key-note D has G for its root, and so on. [Harmonies of Tones and Colours, Diagram XIV - The Modulating Gamut of the Twelve Minor Keys by Fifths1, page 39]
See Also