90 THE NATURE OF MUSIC 



index of the common harmonic report of each tone in 

 correlation with all the other tones. Compare the 

 two sets of numbers. In a) the chord-intervals 7, 9, 

 11 and 13 are respectively 3, 5, ? and 9, which are 

 components of the Dominant. In h) the chord-inter- 

 vals 11 and 13 are respectively 1 and 3 of the Tonic. 

 The large notes in both examples show that both of 

 these chords combine components of' two harmonies ; 

 each contains two roots. 



a) 13 5-135^9 



k± 



i) 



1 3 5 7 9 11 13 

 1 3 5,91 3 



i 



i 



1 3 5 7 9 11 13 



Chords formed by combining the component tones 

 of one harmony I name simple chords ; such, for exam- 

 ple, are all the forms of the major triad. Chords, like 

 those in the above examples, which are formed by com- 

 bining the component tones of two or more harmonies, 

 I name compound chords. 



Tones which relate to but one root I name simple 

 harmonics; such are 1, 3, 5 of the Tonic and 1, 3, 5, 

 7, 9 of the Dominant. Tones, like sol in example a), 

 which simultaneously relate to two roots I name com^ 

 pound harmonics. 



Simple and compound chords and harmonics are 



