and end with the principal note, and are played with great rapidity, and, like all graces, occupy a part of the value of the written note, and are never introduced before it.
|1.||Single Mordent.||Double Mordent.|
The appropriateness of the term Mordent (from mordere, to bite) is found in the suddenness with which the principal note is, as it were, attacked by the dissonant note and immediately released. Walther says its effect is 'like cracking a nut with the teeth,' and the same idea is expressed by the old German term Beisser.
The Mordent may be applied to any note of a chord, as well as to a single note. When this is the case its rendering is as follows—
2. Bach, Sarabande from Suite Française No. 4.
3. Bach, Overture from Partita No. 4.
Sometimes an accidental is added to the sign of the Mordent, thus , or ; the effect of this is to raise the lower or auxiliary note a semitone. This raising takes place in accordance with the rule that a lower auxiliary note should be only a semitone distant from its principal note, and the alteration must be made by the player even when there is no indication of it in the sign (Ex. 4), except in certain understood cases. The exceptions are as follows,—when the note bearing the Mordent is either preceded or followed by a note a whole tone lower (Ex. 5 and 6) and, generally, when the Mordent is applied to either the third or seventh degree of the scale (Ex. 7). In these cases the auxiliary note is played a whole tone distant from its principal.
4. Bach, Organ Fugue in E minor.
5. Air from Suite Française No. 2.
6. Well-tempered Clavier, No. 1, vol. 2.
7. Sarabande from Suite Française No. 5.
[App. p.719 "Example 4. It should be mentioned that many excellent authorities consider it right to play this passage without the accidental, i.e. using A, not A♯, as the auxiliary note of the mordent. See Spitta's 'Bach,' English edition, i. 403, note 89. Example 7, the last note but one should be D, not B."]
The Long Mordent (pincé double) usually consists of five notes, though if applied to a note of great length it may, according to Emanuel Bach, contain more; it must however never fill up the entire value of the note, as the trill does, but must leave time for a sustained principal note at the end (Ex. 8). Its sign is , not to be confounded with , or , the signs for a trill with or without turn.
8. Bach, Sarabande from Partita No. 1.
Besides the above, Emanuel Bach gave the name of Mordent to two other graces, now nearly or quite obsolete. One, called the Abbreviated Mordent (pincé etouffé) was rendered by striking the auxiliary note together with its principal, and instantly releasing it (Ex. 9). This grace, which is identical with the Acciaccatura (see the word), was said by Marpurg to be of great service in playing full chords on the organ, but its employment is condemned by the best modern organists. The other kind, called the Slow Mordent, had no distinctive sign, but was introduced in vocal music at the discretion of the singer, usually at the close of the phrase or before a pause (Ex. 10).