146 



THE NATURE OF MUSIC 



g 



■Z7- 



W 



^ sr 



-^—TSr 



SL 



tS* Z?-^ 



■^—z^- 



Be 



to 



iJe Do 



to 



2)0 



i 



Ti 



^ — ^ — ^ 

 to 



Ti 



In three of these septonal and corresponding 

 octonal scales the two tetrachords in each have the 

 same form: in both Tonic-scales both tetrachords 



have this form, ^^i in both Supertonic-scales 



they have this form, — -^ — : in both Mediant-scales 



they have this form, ^^ . In each of the other 



septonal and octonal scales the forms of the two 

 tetrachords differ, as the examples show. The appear- 

 ance of these tetrachords in all music is most common. 

 For illustrations the reader is referred to Bach's first 

 ** Invention" in two voices and the principal theme 

 of Wagner's "Meistersinger." All the above tetra- 

 chords will be found in the following quotation from 

 Beethoven's E flat Concerto: — 



In his book on "The Music of Antiquity" Gevaert 

 has extricated the Greek modes, their identity and 



