LESSON VI
FOURTH SPECIES
| Fig. 62. |
This species is the same as the second, except that the last note of the measure is tied to the first note of the next, forming a syncopation. As in the second species, the first note of the counterpoint should form a unison, octave or fifth, and when the counterpoint begins on the second half it may also be an imperfect consonance.
When the counterpoint begins on the first half, the second half is treated the same as the second half of succeeding measures, described in the next paragraph.
After the first measure, the second half of the measure should contain a consonance ([Fig. 63a]), the first half a consonance (b), or dissonance (c), preferably the latter, in which case a suspension is formed. This is the most desirable form of syncopation. When the first half contains a dissonance, the counterpoint must descend—or ascend in retardation (d)—one degree to an imperfect consonance (c). When the first half is a consonance, it may be left by a skip to some other chord-tone (e), or by degreewise progression (f). In the latter case the second note is non-harmonic, and therefore should not be used to prepare a syncopation except as in [Fig. 63d] (Retardation of the root in I6).
| Fig. 63. |
When writing three notes to one in the fourth species, the suspension may resolve on the second beat (a), or the third (b). In the latter case, the suspension skips (c) to some other chord-tone, before resolving. The resolution to the leading-tone (d) forms an important exception to this rule. [[Fig. 64.]]
| Fig. 64. |
The fifth may be used in the lower part if it becomes the preparation of a suspension ([Fig. 65a]). It may also be used in the lower part, as in [Fig. 65b], provided it resolves by skipping to the third of the chord.
In skipping from the fifth to the root, or the reverse, in the lower part, do so in an upward direction. The fifth, when treated as an harmonic passing-tone, may, however, be approached either ascending or descending.
| Fig. 65. |
The retardation should be used only when prepared by the leading-tone. It rises a semitone in resolving. [[Fig. 66.]]
| Fig. 66. |
The following dissonant intervals may be used on the first half of the measure:—When the counterpoint is above, the fourth and seventh in suspension, and second and fifth in retardation; and when below, the second in suspension, and the fourth and seventh in retardation. [[Fig. 67.]]
| Fig. 67. |
Consecutive fifths on consecutive strong beats of the measure are good when one of the tones of the second fifth is prepared, as in [Fig. 68.]
| Fig. 68. |
The following cadences are good:
| Fig. 69. |