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b. 19-21

composition: Op. 28 No. 16, Prelude in B♭ minor

Single slurs in A (→FE,FCGE)

Double slurs in EE

..

Starting with the last quaver in bar 19, EE added additional slurs linking the pairs of the L.H. octaves. Similar arbitrary additions are not uncommon in Chopin's works published by Wessel. Similarly in the next bars.

category imprint: Differences between sources

issues: EE revisions

b. 20-21

composition: Op. 28 No. 16, Prelude in B♭ minor

..

Proposed additions concerning the pedalling – see b. 18-21.

category imprint: Editorial revisions

b. 20

composition: Op. 28 No. 16, Prelude in B♭ minor

..

Chopin wrote a cautionary  before a3 at the beginning of the bar. In the main text, we also add a  before the next note, g3.

category imprint: Editorial revisions; Source & stylistic information

issues: Cautionary accidentals

b. 22-23

composition: Op. 28 No. 16, Prelude in B♭ minor

in bar 22 in A (→FEEE)

in bar 23 in FC (→GE)

..

In FC (→GE) Fontana confused b. 22 with b. 23 and placed the  mark a bar too late (in A the  mark in b. 22 falls at the beginning of the line, whereas in FC it is b. 23, identical in the L.H. part, that opens the line).

category imprint: Differences between sources

issues: Errors of FC

b. 22-23

composition: Op. 28 No. 16, Prelude in B♭ minor

b1 & b2 in A & FE2 (→EE)

b1 & b2 in FC (→GE)

b1 & b2 in FE1

..

Before the 7th semiquaver in A there was initially a  (cautionary due to B(1) in the L.H.), which Chopin turned to a . Fontana and the engraver of FE1 misinterpreted that correction by considering it a deletion of the accidental, hence FC (→GE) and FE1 does not contain any accidental before that note, which gives b1. When the figure is repeated an octave higher (at the beginning of b. 23) in FC (→GE), there is also no , which can be explained by an oversight (it would be a puzzling coincidence!) or by a revision, introduced in the belief that it is also here that the alleged crossing-out from b. 22 should be taken into account.
In both places, the naturals visible over the notes were added in FC by H. Scholtz probably in the 1870s.

category imprint: Differences between sources; Corrections & alterations; Source & stylistic information

issues: Corrections in A , Errors resulting from corrections , FE revisions , Errors of FC