240 THE NATURE OF MUSIC 



ond type (second N.B. in example) is named the 

 diminished-small seventh-chord. The third type (last 

 N.B. in example) is named the diminished-diminished 

 seventh-chord, or briefly, the diminished seventh- 

 chord. All other types of seventh-chords are either 

 modifications of these or compound chords. 



Next we exemplify the four positions or forms of a 

 seventh-chord. They are: 1. the ground-form with 

 chord-root as lowest tone; 2. the terce-form with 

 chord-third as lowest tone; 3. the quint-form with 

 chord-fifth as lowest tone; 4. the sept-form with 

 chord-seventh as lowest tone. The four are known 

 respectively as the ground-seventh-chord, chord of the 

 fifth-sixth, chord of the third-fourth, chord of the sec- 

 ond. All appear below in close and open positions. 



Close Open 



js. -^ 



^ jsL _ J2. =: ^. 



^-. — ^ ^fe' — g^ gy ^ \—^. & ^ ^ —^ H 



V. V| Vj V, V, V| V| V, 



Ninth-Chords, We have thus far derived two, the 

 large ninth-chord in major, the small ninth-chord in 

 minor: both are based on the dominant, and each is 

 the original of its peculiar type. 



In Major In Minor 



i^^ 



V9 



The description of a ninth-chord requires three 

 terms, one for the basic triad, one for the superadded 



