[Illustration: Fig. 6.]

Although in two-part counterpoint we have to deal with intervals, rather
than harmonies, still the harmonic progressions represented by these
intervals should be regarded.

The exercises should begin and close with tonic harmony. At the beginning
the unison, fifth or octave, and at the close the unison or octave, are
permitted. [Fig. 7.]

[Illustration: Fig. 7.]

After the first measure it is better to use imperfect consonances only. The
perfect consonances, however, may be used sparingly when a more melodious
counterpoint is thereby obtained.

The unison may be used in the first and last measures only. [Fig. 7.]

All progressions must be diatonic, and parts should not cross.

The repetition of a note in a lower part should be avoided wherever
possible. In a higher part, repetition to the extent of three notes in
succession is allowed.

Do not use more than three thirds or sixths in succession. [Fig. 8.]

[Illustration: Fig. 8.]

Successive similar skips, except the minor third (_a_), in one direction,
are to be avoided. Successive skips of a fourth are good when the tones are