COUNTERPOINT ON A CANTO FERMO The early practice of building polyphonic designs on a voice part confined to a given plain-song or popular melody furnishes the origin for every contrapuntal principle that is not canonic, and soon develops into a canonic principle in itself. When the canto fermo is in notes of equal length and is sung without intermission, it is of course as rigid a mechanical device as an acrostic. Yet it may have artistic value in furnishing a steady rhythm in contrast to suitable free motion in the other parts. When it is in the bass, as in Orlando di Lasso's six-part Regina Coeli, it is apt to cramp the harmony; but when it is in the tenor (its normal place in i6th century music) or any other part, it determines little but the length of the composition. It may or may not appeal to the ear; if not, it at least does no harm, for its restricting influence on the harmony is small if its pace is slower than that of its surround ings. If, on the other hand, its melody is characteristic, or can be enforced by repetition, it may become a powerful means of effect. When the rhythm of the canto fermo is not uniform, or when pauses intervene between its phrases, whether these are different figures or repetitions of one figure in different parts of the scale, the device passes into the region of free art. An early example of its simplest use, as it appears in Josquin's wonderful Miserere, is described in the article Music and in a motet by Lasso. A t 6th century mass, when it is not derived from those secular melodies to which the Council of Trent objected, is often so closely connected with the Gregorian tones, or at least with the themes of some motet appropriate to the holy day for which it was written, that in a Roman Catholic cathedral service the polyphonic music of the best period co-operates with the Gregorian intonations to produce a consistent musical whole with a thematic coherence oddly suggestive of Wagnerian Leitmotif. In later times the Protestant music of Germany attained a similar consistency, under more popular and complex musical conditions, by the use of chorale-tunes; and in Bach's hands the fugal and other treatment of chorale-melody is one of the most varied and expressive of artistic resources. The chorale is not unknown in Handel's Eng lish works. The passage "the kingdoms of the world" in the "Hallelujah Chorus" (down to "and He shall reign for ever and ever") is a magnificent development of the second part of the chorale Wachet auf ("Christians wake, a voice is calling") ; and it would be easy to trace a German or Roman origin for many of the solemn phrases in long notes which in Handel's choruses so often accompany quicker themes.
From the use of an old canto fermo to the invention of an original one is a small step; and merges into the free develop ment of counterpart on a canto fermo the general art of com bining melodies which gives harmony its deepest expression and musical texture its liveliest action. Nor is there any such line to separate polyphonic from non-polyphonic methods of accom panying melody; and Bach's Orgelbiichlein and Brahms's post humous organ-chorales show every conceivable gradation between plain harmony or arpeggio and the most elaborate canon.
In Wagnerian polyphony canonic devices are rare except in such simple moments of anticipation or of communion with nature as we have before the rise of the curtain in the Rheingold and at daybreak in the second act of the Gotterdammerung. On the other hand, the art of combining contrasted themes crowds almost every other kind of musical texture (except tremolos and similar emotional symptoms) into the background, and is itself so trans formed by new harmonic resources, many of which are Wagner's own discovery, that it may almost be said to constitute a new form of art. The influence of this upon instrumental music is as yet helpful only in forms which break away from the limits of the sonata style. Styles which break further away than the omniv orous art of Richard Strauss generally revolt against polyphony altogether. That revolt is suicidal, and polyphony returns every time a brand-new theory of harmony has pitchforked it out. All that is certain is that the two elements by which the music of the future will solve its problem are not those of instrumentation and external expression, but phrase-movement (or musical paragraph ing) and counterpoint. These have always been the elements which suffered from neglect or anarchy in earlier transition periods, and they have always been the elements that gave rationality to the new art to which the transitions led. (D. F. T.)