34. A fugue subject often ends in a different key from that in which it begins. The case most frequently met with is that in which it begins in the tonic and ends in the dominant—
J. S. Bach. Cantata, "Ich hatte viel Bekümmerniss."
Though the leading note of the new key is not introduced here, the construction of the melody in the last two bars clearly indicates the key of G. This is further proved by the answer Bach gives to the subject. In the following examples
J. S. Bach. Cantata, "Singet dem Herrn."
Handel. 'Hercules.'
Schumann. Mass, Op. 147.
the leading note of the dominant key appears in the subject.
35. If the subject be in a minor key, it is very important to remember that the modulation must be to the dominant minor, and not to the dominant major key.
J. S. Bach. 'Matthäus Passion.
Here, though the dominant chord of A minor is, of course, E major, the modulation is not made into that key, but into E minor. Our next example shows a chromatic note in a subject—
Schumann. Fugue, Op. 72, No. 1.
In the second bar of this subject the G sharp, though the leading note of A minor, does not cause a modulation into that key, because it is preceded by B flat, and immediately afterwards contradicted by G natural. The modulation does not take place till the latter half of the fourth bar. Our last example
Rubinstein. 'Paradise Lost.
shows a chromatic note (F sharp) as an auxiliary note, and is therefore similar to the preceding.