Page:Fugue by Ebenezer Prout.djvu/27

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Chap. II.]

Fugue.

9

J. S. Bach. Organ Fugue in C minor.

$\relative c' { \key c \minor \time 4/4 \partial 4 \mark \markup \tiny { ( \italic c ) } c4 | g' g g g | aes2 ~ aes8[ f d f] | b,4 aes' g f | ees d8 ees c4 }$

At (a) the juxtaposition of the minor sixth and major seventh of the scale fixes the key at once. The same result is obtained at (b) by following the arpeggio of the dominant seventh by that of the tonic chord (Harmony, § 219). At (c) we are in doubt till the third bar, though we feel that the key is C, whether the mode will be major or minor; the A flat settles the question in favour of the latter.

32. In our next example

Handel. 'Muzio Scevola.'

$\relative d'' { \key g \minor \time 3/4 \override Score.Rest #'style = #'classical \partial 2 \mark \markup \tiny { ( \italic a ) } d4. d8 | bes4 g r | ees'8[ d c bes a g] | fis[ g a d, e fis] | g[ fis g a bes g] | c[ a d c bes a] | bes }$

the key is fixed by the arpeggio of the tonic chord (compare example (b), § 30).

Mozart. Requiem.

$\relative g { \clef bass \key g \minor \time 4/4 \mark \markup \tiny { ( \italic b ) } r8 g[ g g] g8.[ fis16] fis4 | r8 c'4 c8 c4 bes }$

Here the interval of the diminished fifth followed by B flat shows the key to be G minor. In our last example

Mendelssohn. 'Elijah.'

$\relative a, { \clef bass \key d \minor \time 4/4 \partial 8 \mark \markup \tiny { ( \italic c ) } a8( | bes4) r8 a8( bes4) r8 a( | bes g) cis( d16 e) e8 d r16 d( e f) | f8( g,) r16 d'( e f) f8( a,) r16 d( e f) | f8[( e d cis]) d }$

the first three quavers of the second bar fix the key.

33. Sometimes the subject, instead of being in the key of the tonic, is in that of the dominant throughout, as in the following instances—

J. S. Bach. Cantata, "Ein ungefärbt Gemüthe."

$\relative g { \clef bass \key bes \major \time 3/4 \partial 2 \mark \markup \tiny { ( \italic a ) } g4 g | f8[ e f g a f] | bes4 a g | a d, g ~ | g a8[ g f e] | f e d4 }$

J. S. Bach. Partita in D major.

$\relative c'' { \key d \major \time 9/8 \partial 1 \mark \markup \tiny { ( \italic b ) } cis8 e fis b, d e a, cis | d e16 d cis b e8 a, cis d gis, b | cis }$

Handel. 'Samson.

$\relative c' { \clef tenor \key bes \major \time 4/4 \partial 4 \mark \markup \tiny { ( \italic c ) } c4 | a d g, c | f, bes2 a4 | g4. g8 f2 }$

That we have here the key of the dominant is shown, not only by the signature of the movement, but also (as will be seen in the next chapter) by the interval at which the answer replies.