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b. 25-28

composition: Op. 2, Variations, complete

4 different slurs in AsI

4 longer & 3 shorter slurs in A, literal reading

7 longer slurs in A, contextual interpretation

6 shorter slurs in GE1 (→GE2)

7 shorter slurs in FE, EE 7 GE3

..

The range of the small slurs under the groups of grace notes differs in A; however, they must be accidental inaccuracies, getting bigger as similar marks repeat themselves. The first 4 slurs prove that Chopin almost certainly meant slurs reaching the respective main notes, and this is the interpretation we adopt to the main text. In the editions, the slurs encompassed only the grace notes; moreover, GE1 (→GE2) overlooked the second slur in b. 26 (which was added in the remaining editions).

category imprint: Graphic ambiguousness; Differences between sources

issues: EE revisions , Inaccuracies in GE , Inaccurate slurs in A , Errors in GE , GE revisions , Authentic corrections of FE , FE revisions

b. 25

composition: Op. 2, Variations, complete

il canto in A (→GEEE,FESB)

No indication in FE

..

It seems unlikely that Chopin would have removed from FE1 the second part of the indication on purpose, although it is actually completely unnecessary in this context – due to its position, ben marcato can concern only the topmost R.H. notes. 

category imprint: Differences between sources

issues: Errors in FE

b. 25

composition: Op. 2, Variations, complete

Short accents in A (probable interpretation→GE)

Long accents in A, possible interpretation 

No marks in FE

Vertical accents in EE

..

The accents in A are shorter than the ones over the bass notes in this bar, but the difference is so insignificant that it is uncertain which marks Chopin meant here. The absence of marks in both impressions of FE is either an oversight or a revision – the latter seems more likely, especially in the case of FESB, which was based on GE2, during the final period of its presence on the market, hence when the plates must have already been as worn out as evidenced by the copy presented in our system. Upon seeing the very clear outlines of the removed elements, they could have assumed that the accents over d1 were the remaining elements of the initial, misplaced marks and that it is only the accents over the bass notes that should stay. Anyways, a possible change introduced by Chopin while proofreading FE1 seems less likely than one of the above possibilities. 
The change of the accents over d1 to vertical ones was a typical arbitrary decision of EE.  

category imprint: Differences between sources

issues: Long accents , EE revisions , Errors in FE

b. 25-27

composition: Op. 2, Variations, complete

Long accents in A (→GEFE)

Vertical accents in EE

..

The length of the five accents over each subsequent bass note differs in A – they get shorter with each note; however, it is an inaccuracy of notation, since it is only the last accent that could be considered short (but in a different context). In GE1 (→GE2,FE) the accents are not homogeneous either, but it is most probably also due to graphical reasons – the shortest accent, over e, was squeezed in between the notes of the top voice and could not have been longer. The accents in GE3 are also long, while the ones in FESB could be considered long. By contrast, in EE the horizontal accents were replaced with vertical ones, which was a frequent arbitrary decision in Wessel's publications; a similar change was performed, e.g. in this entire line, see the adjacent note and bar 27.

category imprint: Graphic ambiguousness; Differences between sources

issues: Long accents , EE revisions

b. 26

composition: Op. 2, Variations, complete

g3 in AsI, A & FE1

f3 in GE (→EE,FESB)

..

In GE1 this note was being corrected during the printing process, which is evidenced by the visible – particularly in GE2 – traces of removal of the notehead of g3. Nevertheless, it is uncertain whether the correction was ordered by Chopin – it could have been performed by the reviser – he could have considered the notation of A a mistake. It is also likely that the initially printed g3 was devoid of a ledger line (such mistakes were quite frequent), and the reviser, without consulting the basis, considered the notehead to have been placed too high. Therefore, the authenticity of the version featuring f3 is uncertain; moreover, the fact that g3 was reintroduced into FE1 – undoubtedly by Chopin – proves that the composer eventually opted for g3, even if he were temporarily considering f3.

category imprint: Differences between sources

issues: Chopin's hesitations , GE revisions , Authentic corrections of FE , Authentic corrections of GE