Closely allied to the Mordent is another kind of ornament, called in German the Pralltriller (prallen, to rebound, or bounce), for which term there is no exact equivalent in English, the ornament in question being variously named Passing Shake, Beat, and Inverted Mordent (pincé renversé), none of which designations are very appropriate. The sign for this grace is , the short vertical line being omitted; and it consists, like the Mordent, of three notes, rapidly executed, the auxiliary note being one degree above the principal note instead of below it.
The Pralltriller is characterised by Emanuel Bach as the most agreeable and at the same time the most indispensable of all graces, but also the most difficult. He says that it ought to be made with such extreme rapidity that even when introduced on a very short note, the listener must not be aware of any loss of value.
The proper, and according to some writers the only place for the introduction of the Pralltriller is on the first of two notes which descend diatonically, a position which the Mordent cannot properly occupy. This being the case, there can be no doubt that in such instances as the following, where the Mordent is indicated in a false position, the Pralltriller is in reality intended, and the sign is an error either of the pen or of the press.
12. Mozart, Rondo in D.
Nevertheless, the Mordent is occasionally, though very rarely, met with on a note followed by a note one degree lower, as in the fugue already quoted (Ex. 6). This is however the only instance in Bach's works with which the writer is acquainted.
When the Pralltriller is preceded by an appoggiatura, or a slurred note one degree above the principal note, its entrance is slightly delayed (Ex. 13), and the same is the case if the Mordent is preceded by a note one degree below (Ex. 14).
13. W. F. Bach, Sonata in D.
14. J. S. Bach, Sarabande from Suite Anglaise No. 3.
Emanuel Bach says that if this occurs before a pause the appoggiatura is to be held very long, and the remaining three notes to be 'snapped up' very quickly, thus—
The earlier writers drew a distinction between the Pralltriller and the so-called Schneller (schnellen, to filip). This grace was in all respects identical with the Pralltriller, but it was held that the latter could only occur on a descending diatonic progression (as in Ex. 11), while the Schneller might appear on detached notes. It was also laid down that the Schneller was always to be written in small notes, thus— while the sign only indicated the Pralltriller. Türk observes nevertheless that the best composers have often made use of the sign in cases where the indispensable diatonic progression is absent, and have thus indicated the Pralltriller where the Schneller was really intended. This is however of no consequence, since the two ornaments are essentially the same, and Türk himself ends by saying 'the enormity of this crime may be left for the critics to determine.'
Both Mordent and Pralltriller occur very frequently in the works of Bach and his immediate successors; perhaps the most striking instance of the lavish use of both occurs in the first movement of Bach's 'Capriccio on the departure of a beloved brother,' which though only 17 bars in length contains no fewer than 17 Mordents and 30 Pralltrillers. In modern music the Mordent does not occur, but the Pralltriller and Schneller is frequently employed, as for instance by Beethoven in the first movement of the Sonate Pathétique.
Although the Mordent and Pralltriller are in a sense the opposites of each other, some little confusion has of late arisen in the use of both terms and signs. Certain modern writers have even applied the name of Mordent to the ordinary Turn, as for example Czerny, in his Study op. 740, no. 29; and Hummel, in his Pianoforte School, has given both the name and the sign of the Mordent to the Schneller. This may perhaps be accounted for by the supposition that he referred to the Italian mordente, which, according to Dr. Callcott (Grammar of Music), was the opposite of the German Mordent, and was in fact identical with the Schneller. It is nevertheless strange that Hummel should have neglected to give any description of the Mordent proper.
[ F. T. ]