further show the answering of dominant harmony at the commencement of the subject by tonic harmony at the beginning of the answer. The two subjects are somewhat similar in character.
77. The same point is exemplified in the following—
The subject here begins on the leading note. We shall see when we come to tonal answers that the leading note, excepting when it is merely an auxiliary note of the tonic, is almost invariably considered as the third of the dominant, and answered accordingly by the major third of the tonic (§ 131). This is the case here, and any other answer than that which Bach has given in the subdominant key, will either sacrifice this reply of tonic to dominant, or (if a tonal answer) distort the subject almost beyond recognition. It should be specially noticed that the 'Art of Fugue' from which this example is taken, was expressly written by Bach for the purpose of showing the possibilities of fugal composition; his giving an example of an answer in the subdominant key may therefore be fairly taken as proving, apart from all the other examples we have given, that he considered such an answer correct.
78. The last example we shall give from Bach
is similar in character, and even more pronounced. The subject, except the last note, is formed entirely of dominant harmony,
