A. E. Hull, Modern Harmony (1915)

Alexander Eaglefield Hull was a prolific writer, biographer, and encyclopedist on musical topics. His Modern Harmony: It Explanation and Application (1915) is atypical of his work in its focus on a technical subject, but its source must certainly lie in biographies of Scriabin and Cyril Scott that Hull was preparing at about that time (and published in 1916 and 1919, respectively).

Hull makes his advocacy of contemporary practices crystal clear at the outset:

The swift current of modern musical art during the past ten or fifteen years seems at first glance to have ruthlessly swept away the whole of the theories of the past. The earnest student may well be excused if he is bewildered completely on rising up fresh from his theoretical treatises to plunge into the music of actual life—of the twentieth-century opera houses, concert-halls, and music-rooms. . . .
      The whole of musical history . . . warns one against the too easy acceptance of the neatly turned epithets of persons who are . . . too indifferent to appreciate a new kind of music which claims at once wide sympathies and considerable powers of concentration. . . . Even on short acquaintance these modern musicians have too much method in their so-called “modernity” to be dismissed thus cursorily. It is the greatest possible mistake to view these modern schools as things separate from the art of the past. Indeed, most, of the new traits are legitimate growths out of the art technique of the acknowledged great masters. It does seem as if there were nothing new under the sun. As the principles of the twentieth-century Cubism in painting were well known some 400 years ago, so the modern methods of part-writing and chord-building all find their prototypes time after time in the pages of the great masters of the past.  (1-2; lightly edited)

Then Hull offers up a complaint frequently heard in the century or so from 1850 to 1950:

So much harmony teaching is founded on mere text-book formalities that there is little, if any, appeal to the evidence of the aural intelligence—the real arbiter in all matters of musical taste. It is the empirical method which makes the theory of the music of [recent] composers so difficult, and we cannot suppose that all of the explanations set down herein were present in the composers’ minds at the time of conception, or that they may even be acceptable always to the composers themselves. The system of teaching harmony by attaching names to the chords often produces an altogether false way of regarding music. No chord in itself conveys any meaning whatsoever. It can give a vague impression. . . , but thought in music can only be transmitted by chordal succession and forward movement, and the chord, however wonderfully arranged, has value only in this light. (4-5; emphasis in original)

Consistent with his approach—which simplifies discussion of harmony largely by removing complex labels—Hull has this to say about the dominant ninth and its inversions:

The unnecessarily forbidden appearance of the root in the inversions of the chord of the ninth tends to cramp part-writing, and the prohibition robs diatonic music of some of its most powerful effects. The root, which merely requires judicious placing and arrangement, may appear above the minor or major ninth with great effect. A wide selection of resolutions should be allowed.
For instance:
    (a) Both the major and minor ninth may fall a tone or semitone.
    (b) The ninth may remain.
    (c) The ninth may rise a chromatic semitone.
The case of (b) will be clearer still when the ninth is prepared, thus appearing as a pedal note. In all cases, so long as the ninth is satisfactorily resolved, the other notes are comparatively free. (18-19)

His example for (a)—see the arrow in the second bar—is from a song by Edward MacDowell, a piece so interesting in its treatment of the ninth that I will devote a separate post to it. For (b), see the beginning of the excerpt from the Verdi Requiem. For (c), look at the first chord pair from August Halm's Harmonielehrebuch [sic].

This last example is not in Halm's book. Hull is quoting from Schoenberg's Harmonielehre (1912), complete with the misspelling "Harmonielehrebuch" (properly it would be "Harmonie-Lehrbuch," although that isn't Halm's title, which is simply Harmonielehre).

Halm's example 97c is this. Schoenberg rewrites the progressions under (c). I will discuss his treatment of ninth chords in a separate post.

Halm's Ex 97c is actually meant as a negative example. He regards the V9 resolving to I (see his first examples under 97) as the only correct use of the ninth chord, in contradistinction to the dominant seventh, which he says has a much "softer" character and can move in almost any tonal direction. The two chord pairs under 97c show that one cannot reasonably apply the same traits to the ninth chord (Halm 1900, 118-119).

Reference:

• August Halm, Harmonielehre (1900).  Source: IMSLP; digital facsimile of a copy in the University of North Carolina Chapel Hill library.
• Alexander Eaglefield Hull, Modern Harmony: Its Explanation and Application (1915).    Source: Internet Archive; digital facsimile of a copy in the University of Toronto Library.
• Arnold Schoenberg, Harmonielehre (1912/1922).        Source: Internet Archive; digital facsimile of a copy of unknown provenance.