The Origin and Development of Musical Scales [pp. 324-343]

THE ORIGINV AND DEVELOPMENT OF MUSICAL SCALES. 34I
'tetrachords exhibit perhaps the only traces of its operation. In
-modern music, however, in proportion as polyphony and tonality-which is but the legitimate result of the tendencies induced
by the fact of tone-relation-have developed, and the notes of
the scale have thus acquired new bonds of union with each
,other and with the tonic, the freedom with which equality of
interval has been sought has increased, until the interloper first,
in certain of the chromatic scales, became the indispensable and
powerful minister, and finally, in the scale of equal temperament,
stands lord paramount.
One step in this process seems to Helmholtz to have been
particularly important. Our taste having dictated that the so-called semitone, 16 should be our smallest recognized interval,
-+that fact served to give the semitone an independent definiteness and value. Now, the major seventh, or the note B of the
major scale of C, which corresponds to the Greek Lydian mode,
falls just a semitone below the octave of the tonic, and hence,
altho naturally the most distantly connected to the latter of
-all the notes of the gamut, became with the fuller growth of
tonality the most closely bound to it, and in the character of
,"leading tone" stepped into great prominence. The same
function was performed in descending passages by the Db of
the Dorian mode. The two "leading tones" occur together in
, which Helmholtz calls "almost the only
-isolated and misunderstood remnant of the ancient tonal modes."
The same phenomenon, as mentioned above, is to be found in
Arab music, where several notes, lying quite close to their neighbors, act as routes to them.
To return now to the historic development of modern scales.
-The sudden elevation into power of the tone VII (B of the scale
' As in the last two bars of "And with his stripes we are healed," in the
.Messiah of Handel.
'-i
I Ifv
.the -cadence'
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