It is to be remarked that the arrangement of the overture is written in notes of half the value of those of the orchestral score, with twice the amount in each bar; except the four characteristic wind-chords—tonic, dominant, sub-dominant, and tonic—which are semibreves, as in the original, whenever they occur; in all the rest semiquavers stand for quavers, quavers for crotchets, crotchets for minims, etc., as may be seen by referring to the above examples. The change may possibly have been made in the hope that the players would be more likely to hit the character of the work when playing from the quicker looking notes; or it may have been a vague idea of conforming to a kind of etiquette noticeable in music, church music affecting the longer looking notes, such as semibreves and minims, while orchestral music has the faster looking notes, such as quavers (overtures to 'Coriolan,' 'Leonore,' 'Fidelio,' 'Jessonda,' etc.), and pianoforte music descends to semiquavers—as though to mark the relative degrees of dignity.
The pianoforte arrangement of the scherzo of the 'Midsummer Night's Dream' abounds with happy devices for avoiding rapid repetitions, and for expressing contrasts of wind and strings, and imitating the effect of many orchestral parts which it would be impossible to put into the arrangement in their entirety. One of the happiest passages in the whole work is the arrangement of the passage on the tonic pedal at the end of this movement.
(G pedal, pizzicati bassi, and Corni and Trombe on first beat of each bar.)
Mendelssohn often takes the freedom of slightly altering the details of a quick passage in order to give it greater interest as a pianoforte figure; which seems to be a legitimate development of the theory of the relative idiomatic modes of expression of different instruments, and its adaptation to details.
The method most frequently adopted by him to imitate the effect of the contrast of wind and strings in the same position, is to shift the figure or chords of one of them an octave higher or lower, and to give them respectively to the right and left hands, as in the first part of the music to the first scene of the second act. The continual alternation of the hands in the same position in the Intermezzo after the second act represents the alternation between violins and oboi, and clarinets and flutes.
In the music to the first scene of the third act an important drum roll is represented by a bass shake beginning on the semitone below the principal note, which is much happier than the usual method. In these respects Mendelssohn's principles of arrangement accord with those of Bach and Beethoven, differing only in those respects of treatment of detail which are the result of a more refined sense of the qualities of the pianoforte arising from the long and general cultivation of that instrument.
A still further development in this direction is found in the arrangement by Herr Brahms of his pianoforte quintett in F minor (op. 34) as a sonata for two pianofortes. In this the main object seems to have been to balance the work of the two pianofortes. Sometimes the first pianoforte, and sometimes the second has the original pianoforte part for pages together, and sometimes for a few bars at a time, but whenever the nature of the passages admits of it, the materials are distributed evenly between the two instruments. There are some changes—such as the addition of a bar in two places in the first movement, and the change of an accidental in the last—which must be referred to critical considerations, and have nothing to do with arrangement.
The technical changes in the arrangement are the occasional development of a free inner part out of the materials of the original without further change in the harmonies, the filling up of rhythm-marking chords of the strings, frequent reinforcement of the bass by doubling, and, which is especially noticeable, frequent doubling of both melodies and parts of important figures. It is this latter peculiarity which especially marks the adaptation of certain tendencies of modern pianoforte-playing to arrangement,—the tendency, namely, to double all the parts possible, to fill up chords to the utmost, and to distribute the notes over a wider space, with greater regard to their tonal relations than formerly, and by every means to enlarge the scope and effective power of the instrument, at the same time breaking down all the obstructions and restrictions which the old dogmas of style in playing placed in the way of its development.
Another admirable instance of this kind is the arrangement by Herr Brahms of a gavotte of Gluck's in A; which however in its new form is as much marked by the personality of the arranger as that of the composer—a dangerous precedent for ordinary arrangers.
The most remarkable instance of the adaptation of the resources of modern pianoforte-playing to arrangement, is that by Tausig of Bach's toccata and fugue for the organ in D, 'zum Conzertvortrag frei bearbeitet.' The difficulty in such a case is to keep up the balance of the enlarged scale throughout. Tausig's perfect mastery