A sketchleaf containing some of the greatest music in all Mozart, and probably the most important single leaf of autograph music by the composer to be offered at auction in recent years. It has, in addition, not been available for consultation by modern Mozart scholarship.

It is the only autograph manuscript relating to the Sinfonia Concertante left in private hands.

The identification of the fragmentary horn music on the Mozarteum strip as originally belonging to the present autograph has, so far as we know, up until now eluded Mozart scholarship, and represents an important Mozart discovery.

Mozart's great Sinfonia concertante, in effect a double concerto for violin and viola, represents a milestone in Mozart's creative output, a work of truly explosive emotional power and intensity, which he may later perhaps have equalled but never surpassed. The circumstances of its composition are sadly unknown. Dating sometime from the end of Mozart's Salzburg years, it is the composer's finest essay in a genre of instrumental music - the symphonie concertante - with which he doubtless become well acquainted during his stay in Paris and Mannheim in 1778, through the works of such composers as Cambini, Cannabich and Carl Stamitz. In fact, no few than six such works were attempted by Mozart at this time and a little later: these include the one for four wind instruments, K.297B and two impressive fragments, one in D for piano and violin, K.Anh.56/K.315f, and one in A for violin, viola and violoncello (K.Anh.104/320e), this last a magnificent torso of 134 bars whose abandonment possibly paved the way for the composition of K.364. Mozart's E flat masterwork for violin and viola, however, sublimates and distils all his recent musical experiences to create a work which not only revels in a new-found creative confidence but also displays an astonishing deepening of expressive and emotional power. No doubt Mozart's biography played its part here too: it is certainly tempting to view the sublimely tragic C-minor Andante as a kind of requiem for Mozart's mother, Anna Maria, who died in Paris in the summer of 1778. And can we see in the concertante's cadenzas a musical representation of the complex, intertwined, competitive, and even agonising, relationship of Mozart and his father Leopold? At any rate, it is not difficult to imagine a performance of the work with, as violin soloist, Mozart's father, author of the eighteenth-century's most important violin-playing treatise, and, as viola soloist, the composer himself (although an excellent fiddle player, the viola was his preferred string instrument). 
 
The autograph score of K.364 is lost, and only the following autograph sources survive: the present sketch; two sketches for the slow movement cadenza, contained on the verso of a leaf bearing a draft for the original close of the first movement, bb. 349-357 [Houghton Library, Harvard University, Ms Mus 177]; and a fair copy of the cadenzas for the first and second movement [Veste Coburg, Autographensammlung, V, 11 09, 9]. Furthermore it may be noted that no autograph cadenzas for Mozart's five violin concertos (K.207, 211, 216, 218, 219) survive.

The sketch provides a remarkable glimpse into the private world of Mozart's creativity. Clearly written down at something approaching breakneck speed, its hasty note forms reveal that it was intended for the composer's eyes only (indeed, it has only survived - piggy-backed to eternity, as it were - because it was written down on the reverse side of another manuscript considered usable and worth preserving - that of the horn parts on the recto, even if the work to which these belonged was unknown). Remarkably, the present sketch differs relatively little from Mozart's autograph fair copy: a few divergences in articulation can be seen as well as some minor differences affecting pitch, for instance in bb.10 and 25 of the cadenza. A very typical piece of Mozartian technical wizardry is on display too in the sketch: the notation of the viola part in D major (see the two-sharp key signature in the very first bar [= the 'pause' bar before the cadenza, b.338 of the complete movement]). To lift the tone of the viola out of that of the accompanying orchestral sound, and to give it a brilliance on a par with that of the solo violin, the instrument was tuned a semitone higher (the so-called scordatura tuning), its part being notated a semitone lower.

Not the least extraordinary feature of the leaf are the two autograph horn parts for two as yet unidentified compositions in F and E flat - possibly contredanses - which Mozart notated first, on the recto. Surviving complete on the leaf is the horn I part for both compositions (24 and 16 bars in length, respectively); of the horn II part, only the first 16 bars for the first piece survive here, due to the excision of the lower portion of the leaf. We can reveal that the remaining 8 bars of the horn II part for the first piece in F and bb.1-12 (first note) of the music of the horn II part for the second piece in E flat are contained on a three-stave strip, measuring c.5.5-6 x 19cm, now in the Internationale Stiftung Mozarteum, Salzburg, but once part of the present autograph. Although not unrecorded in the Mozart literature (being described as a horn part, not in Köchel ["KV deest. Hornstimme"], in a 1988 article by Rudolph Angermüller), its connection to the present cadenza leaf has until now remained unnoticed. The whereabouts of the last four and a half bars of the horn II part for the second piece in E flat are currently unknown. The verso of the Mozarteum fragment contains a rather flowery verse inscription by Carl August André (1806-1887), a son of the great Offenbach publisher Johann Anton André, who had purchased en bloc Mozart's autographs from his widow, Constanze, in 1800. Carl August's inscription, written in the same blue ink as his inscriptions "Mozart's eigne Handschrift" on the present manuscript - we must now visualise as occupying the space in the present manuscript following the sublime cadenza: 

...Was könnt ich Schöneres zum Andenken geben
   Als Skizzen von dem Meister der Töne hoch erheben,
   Von MOZART's edlem Wirken, dies Blatt von seiner Hand,
   Die in der flücht'gen Zeichnung die schönsten Kränzen wand.
   Die eine Seite zeiget, wie er noch abgeschrieben
   Der eigenen Schöpfung Stimmen, die ewig neu geblieben,
   Die andere, die Cadenze, mit freundlich schnöder Miene,
   Ein Tonstück für Viola und für Violine.
   O, möchte dieses Blatt, wenn wir getrennt im Leben
   So sehr erfreun, wie ich es gerne hingegeben.

                                                                              André
                                        Frankfurt a.M. Haus 'MOZART'
                                                                9 Januar. 1851.

The strikingly different appearance of the horn parts and the cadenza sketch, can be explained on two grounds. First, the former represents a calligraphic performing part, intended to be read by others, while the latter is a private document for Mozart alone. And second, the horn parts date from sometime before the cadenza (they were thus the first things to be written on the present leaf - on the recto, not the verso, as stated in NMA X/30/3, Kritischer Bericht, p.13). While the particular forms of the 'p' and 'f' in the dynamic markings 'pia:' and 'for:' in the horn parts suggest a dating sometime between 1775 and 1778, this time frame can possibly be narrowed to 1776-1777 on account of the paper - a Salzburg type, found elsewhere only in the autographs of the Concerto in F for Three Pianos, K.242, dated February 1776, and of the Litany K.243, dated March 1776, and, as such, unlikely to have been taken by Mozart with him on his journey to Paris (September 1777-January 1779).

We are most grateful to John Arthur for his identification of the music of the Mozarteum strip as a continuation of the horn parts on the present manuscript, and for his dating of the horn parts.