It is a striking fact that in the history of the same theoretical scale among the Greeks there arose likewise an alternative usage involving the difference of a semitone in one of its steps, and that the note affected was the same in Greece as in China. This was the note since called Si in the diatonic scale, and its differing pitch was the basis of the distinction between the disjoined and conjoined tetrachords of Greek theory.[1] The double intonation continued during the middle ages, and was the germ from which has grown the whole system of modern modulation. While it is open to us to suppose that the appearance of the same phenomenon in Chinese musical history is due to the influence of Western civilization, we are not told that the Mongols brought the varying usage with them, but that it arose when their scale met that of China. Perhaps both the theory of conjoined and disjoined tetrachords and the story of the Mongol scale are equally unreal hypotheses invented to explain the expedients by which the Greeks and the Chinese met each in their own way a practical difficulty arising in diatonic music. The notion of the diatonic order as a product of the fifth progression involves the conception of Fa as the generating note, the origin of the others. If we assume that this position of
- ↑ Cf. Stainer and Barrett's Dictionary of Musical Terms, art. Greek Music. The later Greek scale had a compass of two octaves, like that of our songs; but since it was formed theoretically of four Dorian tetrachords (a sequence of a hemitone and two tones) with two added tones, the range of the two differs as follows: K Ch PT(PT) pK P T(pT) P K Ki T Y K Ch Ki T Y K La Si Do Re Mi Fa Sol La ( ) Si Do Re Mi Fa Sol La t - h . t t h t t t . h t . t h- t t h . t t t - Alternative position or conjoined tetrachord. The two middle tetrachords might either have a note in common (syncmmenon, conjoined) or be separated by a tone (diezcugmenon, disjoined). The comparison of the two scales shows that in the one case the note corresponding to pien-Tche was a semitone, and in the other a tone below the next higher note. In Chinese music the lower octave of pien-Tche seems also to have been lowered in pitch a semitone. This was not the case in the Greek scale. The note does not occur in our songs but is given the lower position in two (IV and VII) of Barrow's collection.
