smoother melodic progression is thereby obtained; and when both thirds are
in outer parts, each should be approached and left stepwise in one
direction (Fig. 87). The doubling of the fifth is, of course, impossible,
since it necessitates the omission of the third.

[Illustration: Fig. 87.]

All triads may be used in their first inversion.

Diminished and augmented triads, however, are best used in their first
inversion.

The six-four chord may be used at the close as the cadencing tonic six-four
chord. Do not approach the root and fifth in similar motion, as at _b_.
[Fig. 88.]

[Illustration: Fig. 88.]

The dominant seventh may be used in any but its second inversion, the
fifth being omitted.[2] The seventh requires no preparation. Other chords
of the seventh are better not used until second species and later.

If possible, let the chord in the first measure appear complete. The last
chord but one should be complete, unless some form of V or V_7 is used.
[Fig. 89.]

[2] In severely strict counterpoint all parts above the lowest must be
consonant with it. Dissonances, when entering simultaneously with it,
must be treated as suspensions, and when used in the progression of a
part from one chord to another, should be treated as passing-tones or