Page:Fugue by Ebenezer Prout.djvu/108

90 really a second exposition in the same two keys (generally tonic and dominant) as the first, but with important differences. The chief of these are that in the counter-exposition the voices which before had the subject now have the answer, and vice versa; and that frequently the answer leads and the subject replies. In fugues 1 and 11 of the 'Wohltemperirtes Clavier' will be seen examples of the former, and in Nos. 26 and 33 of the same work, illustrations of the latter. Sometimes, as in the first fugue, the counter-exposition follows immediately on the close of the exposition; at others (as in Fugue 11) it is separated from it by an episode. To save space, we simply refer to these pieces without quoting them; we may fairly suppose that everyone who wishes to study fugal construction has a copy of the 'Forty-Eight' by him for reference. If not, the sooner he gets one, the better. It should be added that in the counter-exposition the entries of the voices are generally accompanied by free counterpoint in the other voices; it is seldom that the leading voice in the counter-exposition is found (as in the exposition) unaccompanied.

208. In many cases, when there is a counter-exposition, it is only partial; that is to say, not all the voices of the fugue take part in it. For example, in Fugue 38 of the 'Wohltemperirtes Clavier,' which is for three voices, the exposition, which ends at the 11th bar, is followed by the first episode. In bar 14 begins the counter-exposition. The bass, which before had the subject, now leads with the answer, which is now real, though it was at first tonal (§ 109). Before the completion of the answer by the bass, the treble, which before had the answer, enters with the subject (bar 16), but the close of the subject in the treble is followed by the second episode, the alto not entering in the counter-exposition with either the subject or answer, and having only free counterpoint throughout.

209. In the passage just referred to, we said that the treble entered with the subject "before the completion of the answer by the bass"; and this leads us to notice a feature very often to be met with when there is a counter-exposition. In many cases this portion of the work is used to introduce the first stretto,—that is to say, in the counter-exposition, the entries of the subject are closer together than in the first exposition. For instance, in the fugue just noticed, the answer enters in the exposition three bars later than the subject; but in the counter-exposition it is only two bars later. In the first fugue of the 'Forty-Eight' the answer in the counter-exposition follows the subject at only one crochet's distance, instead of a bar and a half; and in the 31st fugue of the same work the counter-exposition takes the form of a canon at one bar's distance first at the fifth below, between tenor and bass, and then at the fourth above, between alto and treble. Considerably more latitude is allowed as to the entries in the counter-exposition than in the exposition.

210. Occasionally we find a counter-exposition by inversion.