Preface

VIII
in Agricola’s hand is of particular inter-
est in this context: in 1738 he copied
four fugues in C, c, D and d (Staatsbib-
liothek zu Berlin, Mus. ms. Bach P 595)
that are early versions of the Well-Tem-
pered Clavier II-fugues in Ck, c, Eb and
d respectively. This suggests that the
work evolved from Bach’s gathering to-
gether of further teaching material for
his students. Indeed, eleven of the forty-
eight movements – or nearly a quarter
of the entire collection – are known to
have been worked out from early ver-
sions, and doubtless many more move-
ments originated in early versions that
we have yet to discover.
Source Tradition B: (The lost Autograph
“[B]” and its dependent copies)
The absence of a definitive fair copy in
Bach’s hand also means that we do not
have reliable information regarding
what he called this collection. As al-
ready mentioned, “A” lacks the title-
page. The surviving copies derived from
it consistently suggest that Bach per-
haps never wrote one for this set. The
earliest copy with a title-page is that
produced by Bach’s future son-in-law
Johann Christoph Altnickol, who began
his studies with Bach in 1744 (Staats-
bibliothek zu Berlin, Mus. Ms. Bach P
430). For his carefully-produced fair
copy “B1”, Altnickol supplies the fol-
lowing title: Des Wohltemperirten Cla-
viers / Zweyter Theil, / besthehend / In /
Præludien und Fugen / durch / alle /
Tone und Semitonien / verfertiget / von /
Johann Sebastian Bach, / Königlich
Pohlnisch und Churfurstl. Sächs. / Hoff
Compositeur Capellmeister / und Di-
rectore Chori Musici / In Leipzig. (The
Well-Tempered Clavier, Second Part,
consisting of Preludes and Fugues in all
the tones and semitones, written by Jo-
hann Sebastian Bach, Royal Polish and
Electoral Saxon Court Composer,
Capellmeister and Directore Chori Mu-
sici in Leipzig.) Although this is much
simpler than what Bach wrote for part I,
there is every reason to believe that this
modest description of the work originat-
ed from the composer himself. The date
of the copy was inscribed after the last
fugue: Scr[ipsit] Altnickol / a[nn]o.
1744. Apart from being the earliest
complete copy to include a title-page,
this copy by Altnickol tells us three fur-
ther important facts. Firstly, that Alt-
nickol’s model was not “A” but another,
now lost, autograph set “[B]”. Secondly,
that Bach appears to have monitored Al-
tnickol’s copying, sometimes instructing
him to make notational changes as he
was copying from Bach’s manuscript.
Finally, the manuscript contains numer-
ous corrections, ranging from Altnick-
ol’s own corrections of errors to later
amendments of a musical nature, in-
cluding some clearly identifiable as
Bach’s handwriting.
On the first point, it is essential to un-
derstand why Bach shifted his attention
from the London autograph “A” com-
pleted in 1742 to the set that at that
point presumably consisted of well-de-
veloped drafts and sketches. Alfred Dürr
suggests that, sometime between 1742
and 1744, Bach perhaps gave away the
former source to his eldest son, Wilhelm
Friedemann Bach, whose handwritten
additions can be identified on some pag-
es, and that it became necessary for
Bach to bring the incomplete set to the
same state as the former. It is also plau-
sible that Bach simply wanted to have
another complete copy, as it seems to
have been his standard practice not to
lend his personal reference copy to his
students. Whatever the truth may be, it
appears that before Altnickol started
copying from the latter his model had
already been updated. Bach’s revision
work included all the Stage 3 move-
ments and the expansion of two move-
ments from Stage 1, namely Prelude d
and Fugue e, respectively interpolating
8 new measures and extending the final
section of the fugue by 16 measures.
Thus by 1744 this set “[B]” would have
looked as the more up-to-date copy in
Bach’s household, even though many
movements in “A” still remained in the
later version, as Bach apparently did not
revise every movement in the other set.
The second point – Bach’s copying in-
structions to Altnickol – fills an impor-
tant gap in our information about the
state of Bach’s lost autograph “[B]”.
Altnickol was instructed for instance to
rewrite Fugue in bb and Prelude in b in
double note-values as Bach himself had
done in “A”, namely converting from 4
to 1 and from 3 to X respectively. In a
sense, this feature demonstrates Bach’s
efforts to make Altnickol’s copy an up-
to-date fair copy.
The third and last point – concerning
the later revisions – is complicated by
the fact that the manuscript not only re-
ceived thorough revisions from Altnick-
ol and Bach, but also from one of its lat-
er owners, Friedrich August Grasnick
(1795–1877), who transferred the
readings of another manuscript tradi-
tion by referring to the so-called Kirn-
berger personal copy (Staatsbibliothek
zu Berlin, Am. B. 57). All the revisions
have been systematically studied as re-
gards their calligraphy, the characteris-
tics of the quill and the shades of ink
used, and the genealogical origin and
musical nature of the revised readings.
The most rewarding information re-
trieved from this phase of study con-
cerns an extra layer of revision by Bach
that is found exclusively in this copy,
throwing fascinating light on how Bach
taught Altnickol. Since the details of the
findings are explained in the Comments
at the end of this volume, it may be suf-
ficient here to mention that from 1744
onwards this second autograph set
“[B]” and Altnickol’s 1744 copy “B1”
became the two most important sources
in Bach’s household for his other stu-
dents to copy from.
What emerges from this study is that
Bach never saw the end of the process of
improvement, which continued down
through students’ copies, making the
task of identifying Bach’s latest thoughts
very daunting. As far as can be traced,
Bach did not make a definitive fair copy
beyond what he had done with “A” and
“B1”. In this way, the Well-tempered
Clavier, Part II, is comparable to the
other unpublished anthologies compiled
during his lifetime such as the Orgel-
büchlein and the ‘Great Eighteen cho-
rales’.
Notes on this Edition
The present edition attempts to put to-
gether Bach’s latest thoughts on the col-