[Illustration: Example 48. Fragment of Mozart.]
The Antecedent is a regular four-measure phrase, with semicadence (made on the tonic chord, but with 3d as uppermost tone); the Consequent is a six-measure phrase, with perfect cadence, and is repeated, with partial change of register. The whole is a "period with repeated Consequent."
A somewhat elaborate example of extension by detail-repetition is seen in the following (Chopin, Mazurka No. 20, op. 30, No. 3—see the original):
[Illustration: Example 49. Fragment of Chopin.]
[Illustration: Example 49 continued.]
These sixteen measures are the product out of eight measures, by extension; that is, they are reducible to a simple period-form (as may be verified by omitting the passages indicated under dotted lines), and they represent in reality nothing more than its manipulation and development. The original 8-measure period makes a complete musical sentence, and was so devised in the mind of the composer, without the extensions. The method of manipulation is ingenious; observe the variety obtained by the striking dynamic changes from ff to pp; and, hand in hand with these, the changes from major to minor, and back (as shown by the inflection of b-flat to b-double-flat). These are first applied to members only, of the Antecedent, as indicated by the brackets a and b, and then to the entire Consequent phrase. Observe, also, that in the repeated form of the latter, the rhythm is modified to a smoother form, during two measures. The result here achieved is constant Unity and constant Variety from almost every point of view, admirably counterbalanced.