Plain-song. PLAIN-CHANT, GREGORIAN CHANT, or GREGORIAN MUSIC, is the music used in the Christian church of the West from the earliest times, still in use in all Roman Catholic churches, and extensively revived since the rise of the High Church party in the English Church. Many good musicians, however, consider its interest as antiquarian rather than musical. Its distinguishing points are (1) its recitative-like character, as opposed to what was styled musica mensurata—i.e. barred music, with a marked and regular rhythm, which was the essential point of ancient Greek music, and more or less of nearly all modern music; (2) the modes, or scales, in which it is written, which are more numerous and varied than the modern major and minor; and (3) its being (originally) sung in unison, though much of it is susceptible of treatment in harmony, and is now frequently so heard. It used to be stated also that the notes in it were all of equal length, but this view is now generally repudiated and condemned. It embraces music for all parts of the Roman services, from the Accents (nearly in monotonous) proper to the various readings to the more elaborate melodies of the antiphons and hymns, and the various parts of the mass. The best known and most ancient of all is the music of the eight Tones sung to the Psalms, commonly called the Gregorian Tones. As to the origin of these many different views prevail, some ascribing them to a Greek, some to a Hebrew source, others to the early Christians; there seems some probability, though there is no direct evidence, that they were actually derived from the music of the temple service. As at first plain-song was handed down orally only, and the early systems of nota- tion were very defective, it is impossible to determine how far it may have been corrupted. It was first reduced to system by St Ambrose (died 397), but much more extensively by St Gregory the Great, towards the end of the 6th century. There have of course been large additions since. How he noted the music is uncertain; the early notation and rules of plain-song were so complicated that it is said ten years' study were necessary to acquire a mastery of them. Local varieties of the proper melodies gradually sprang up, almost every diocese having an office-book peculiar to itself—e.g. the antiphonary and gradual of Sarum, said to be one of the purest. The earliest known existing record of plain-song is the Antiphonarium, or rather Gradual, in the library of the monastery of St Gall in Switzerland, probably of the 9th or 10th century. Various directories have been published, notably that begun by Palestrina and finished by Gnidetti; the latest, issued under sanction of the pope, is the great series published at Ratisbon by Pustet, beginning in 1871 with the Gradual. The music is still always printed in the old square notes on a stave of four lines. At the Reformation the Gregorian music was adapted to the new vernacular services of the English Church by John Marbeck, who published in 1550 The Book of Common Praier noted; and his arrangement is still in use in cathedral services. Anglican Chants (q.v.) are modelled on the Gregorian psalm tones.
The modes, or scales, of plain-song require some explanation. Their variety has been acknowledged by first-rate authority as affording greater resource of expression than our major and minor modes; and music has been written in them by great modern composers—e.g. the 'Hymn in the Lydian Mode' in Beethoven's Quartet, op. 132. They
SPECIMEN OF ANTIPHON, LEADING TO A PSALM, SET TO THE FIRST TONE, FROM THE RATISBON 'VESPERAL,' TRANSLATED AND IN MODERN NOTATION.
The an - gel said un - to him, Thou shalt call his name John.
Thou shalt have joy and glad - ness, and ma - ny shall re - joice at his birth.
Intonation
(used only before verse 1).
Reciting Note
(usually longer
dwelt on).
Mediation, Festal form.
PSALM CXII. Bles - sed is the man that fear - eth the Lord.
Second Reciting Note.
Ending, 1st form.
(Tones 3, 4, 7, and 8 have more than one form of ending.)
He hath great de - light in his com - mand - ments.
Reciting Note.
Mediation.
Verse 2. His seed shall be might - y up - on earth, &c. were derived from, though it is not certain that they were identical with, the Greek diatonic scales, after which they have been named. The principle of their formation is that each of the seven natural sounds of the diatonic scale forms the keynote, or 'final' of a mode, which embraced that note and the seven above it. (The melodies rarely exceeded an octave, and no flats or sharps are found except an occasional B flat.) This would give us seven modes; but to each of these is attached another, in which the melody, while having the same final or keynote, instead of ascending to the octave above, ranges from the fourth below it to the fifth above. The former are called the authentic modes, the latter plagal. The difference of the modes, and the effect of the melodies in them, is owing, it will be noticed, to the various positions of the two semitones in the scales. The difference between an authentic and a plagal melody may be illustrated from two psalm-tunes—Newton or New London, and the Old Hundredth, in the first of which the melody lies between the keynote and its octave, but in the other between the fourth below and the fifth above the keynote. But while the whole fourteen modes are enumerated, for the sake of completeness in theory, two of them are universally rejected in practice as defective—the two having B as their keynote. The modes are, then, arranged in pairs as follows. The 1st or Dorian (authentic) embraces the notes from D on the middle line of the bass stave to the D above, and has its keynote on D; the 2d or Hypo-dorian (plagal) has the same keynote, but its compass is from the A below to the A above it; the 3d or Phrygian (authentic) and its corresponding plagal mode, the 4th or Hypo-phrygian, have similarly their keynotes on the E of the third space of the bass stave; the 5th or Lydian and 6th or Hypo-lydian have F for final; the 7th or Mixo-lydian and 8th or Hypo-mixo-lydian have G; the 9th or Æolian and 10th or Hypo-æolian end on A; then come the rejected modes on B, styled the Mixo-locrian and Hypo-mixo-locrian; then the Ionian or Iastian and Hypo-ionian or Hypo-istian on C, numbered variously as 11th and 12th, or 13th and 14th, according to the rejection or inclusion of the two preceding. The Ionian is the modern major mode. St Ambrose's arrangement of the melodies was said to have been confined to the 1st, 3d, 5th, and 7th modes (authentic); while the relative plagal modes, 2d, 4th, 6th, and 8th, were added by St Gregory. In these are written the correspondingly numbered eight psalm tones; the Peregrine Tone, used only for the psalm In exitu Israel, is in the 9th mode. The other modes were finally added in the 8th century under Charlemagne. Each mode has its reciting note, or Dominant—not to be confounded with the modern term in harmony.
Various specimens of plain-song hymn melodies will be found in Hymns Ancient and Modern—e.g. No. 14, the vespers hymn of St Ambrose, 'O Lux beata Trinitas;' and No. 96, the hymn of Fortunatus, 'Vexilla Regis prodeunt,' which may be studied in a different treatment by Gounod in the 'March to Calvary' in his Redemption.
See the Rev. Thomas Helmore's Manual, Brief Directory, and Primer of Plain-song; various articles by Mr W. S. Rockstro in Grove's Dictionary of Music; and the Magister Choralis, by Rev. F. X. Haberl (trans. by Rev. N. Donnelly, Ratisbon, 1877). An edition of the official Roman Directorium was printed in 1874, also at Ratisbon, by Pustet. See also the article HARMONY.