Op. 45, Prelude in C♯ minor

The title given above can be seen on the first page of the musical text. The collective cover of Wessel & Co's Complete Collection of the Compositions of Frederic Chopin only has "Prelude". 

EE1 was based on FE1 and was subject to a thorough revision, in which numerous errors and inaccuracies were corrected. That conclusion, evident from the analysis of the sources, finds additional confirmation in a letter of Ignaz Moscheles written to Maurice Schlesinger on 2nd Nov. 1842, in which Moscheles remarked that he had been correcting copies of the French editions of Op. 44-49, including the Prelude, for Wessel.

Most revisions consisted in adding or correcting accidentals; for instance, signs were added before the last three quavers in bars 28, 31 and 37,
 (c³) was changed to  (c³) in bar 43 and  (B₁) to  (B₁) in bar 56. The notation of the rhythm in bar 8 and analogous bars was also corrected, and that makes EE1 the only first edition in which the initial octave is always  correctly written as far as division into voices (parts) is concerned. 

Numerous additions of accidentals make EE1 resemble the version of FE2. However, several instances in which the consistent version of FE1 and EE1 differs from FE2, e.g. lack of  (cautionary, yet justified) before c in bar 64 and d in bar 87, slurs in bars 61-62,  in bars 64-65 or dashes marking the scope of cresc. in bars 65-66, allow us to rule out the possibility that EE1 was based on FE2. Also, the correct placement of the  mark in bar  5, which is placed imprecisely in FE1 and erroneously (in bar 4) in FE2, proves that EE1 was not derived from FE2.

Some of the changes introduced in EE1 show evident misunderstanding of Chopin's intentions, e.g. adding an augmenting dot in bar 85 or the note
g and ties in bars 90-91.