142. In the following passages we see an augmented fourth in the subject becoming a major third in the answer.
J. S. Bach. Cantata, "Ihr werdet weinen und heulen."
Notice that here the augmented second and the minor seventh in the second bar are retained in the answer, and the change of interval comes where the modulation takes place.
Albrechtsberger.
This is a similar instance to the last. The form of the melody renders it impossible to introduce the modulation earlier.
Mozart. Mass in C, No. 4.
This is a curious example, because Mozart by the way he answers the subject implies three modulations—to the dominant and back in bar 2, and again to the dominant at the end. It would have been simpler to treat the first F sharp, which is almost immediately contradicted, as a chromatic note, and to have given the answer the following form—
which would have been equally correct here (compare § 65).
143. Our next example shows the converse case, a major third in the subject becoming an augmented fourth in the answer.
Albrechtsberger.
