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b. 77-80

composition: Op. 10 No 12, Etude in C minor

Slur in A, literal reading

Interpretated slur in A (→FE→GE1), and slur in EE & GE2 (→GE3GE4)

Our suggestion

..

The slur in A in bar 77, the last in the line, suggests a continuation in the next bar, yet there is no relevant slur in bar 78. In FE (→GE1) the ambiguous ending of the slur was reproduced, which was already avoided in EE and subsequent GE,s (the slur ends on the last semiquaver). In the main text we give the slur after the slur in analogous bars 79-80, probably added by Chopin at the time of proofreading FE.

category imprint: Graphic ambiguousness; Interpretations within context; Differences between sources

issues: Inaccurate slurs in A , Authentic corrections of FE

b. 77

composition: Op. 10 No 12, Etude in C minor

..

We add a cautionary  before b. The addition was already performed in GE3 (→GE4), in which a  before B in the 4th group of semiquavers was added. 

category imprint: Differences between sources; Editorial revisions

issues: GE revisions

b. 77

composition: Op. 10 No 12, Etude in C minor

..

In A (→FEEE) there is no  lowering to d. This patent inaccuracy was corrected in GE. In the identical situation in bar 79  is included in all sources.  

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves

b. 77

composition: Op. 10 No 12, Etude in C minor

Dot in A

No mark in FE (→GE,EE

..

According to us, omission is the most plausible reason for overlooking the staccato dot in the lower voice in FE (→GE,EE). Cf. the note to the L.H. and bars 79-81.

category imprint: Differences between sources

issues: Errors in FE

b. 77

composition: Op. 10 No 12, Etude in C minor

Wedge in A

No mark in FE (→GE)

Dot in EE

..

In the main text we give the wedge, most probably omitted in FE (→GE) due to the engraver's oversight. It is unclear on which basis a dot was added here in EE.

category imprint: Differences between sources

issues: EE revisions , Errors in FE , Wedges