3g4 ii;cTt;Ri: xxxnr. 



making a tone or note; these terms are, however, sometimes employed with 

 various subordinate distinctions and limitations. The five additional sounds 

 have no separate names, but they are denominated from the neigh- 

 bouring notes on either side, Avith the addition of the term sharp or flat, 

 accordingly as they are a semitone higher or lower than the notes of 

 which they bear the names. 



For still further variety, we sometimes cbange the place of the middle 

 note of each triad, placing the minor third, or the interval expressed by the 

 ratio of 5 to 6, below the major, which is in the ratio of 4 to 5; and the 

 scale thus formed is called the scale of the minor mode, in contradistinction 

 to the major, the three principal thirds being depressed a semitone. Some- 

 times, however, the alteration is made in the third of the key note only, 

 especially in ascending, in order to retain the seventh of the major scale 

 which leads so naturally into the octave, as to be sometimes called the 

 characteristic semitone of the key; and it is for this reason, that the triad, 

 in which it is found, is called the accord of the dominant, which, in all regu- 

 lar compositions, immediately precedes the termination in the key note. 



The major and minor triads, with the discord of the flat seventh, may be 

 considered as constituting the foundation of all essential harmonies. The 

 flat seventh is principally used with the major triad, in transitions from the 

 fundamental key into its fourth, to which that seventh naturally belongs as 

 a concord; so that it serves to introduce the new key, by strongly marking 

 the particular note in which it differs from the old one ; and in such cases the 

 flat seventh always descends into, or is followed by, the third of the new key, 

 and the third of the first triad ascends into the new key note. Other dis- 

 cords are also sometimes introduced, but they are in general either partial 

 continuations of a preceding, or anticipations of a following accord. Two 

 difi'erent parts of a harmony are never allowed, in regular and serious com- 

 positions, to accompany each other in successive octaves or fifths, since 

 such a succession is found to produce a disagreeable monotony of effect, 

 except when a series of octaves is continue for some time, so as to be con- 

 sidered as a repetition of the same part. 



These are almost the only principles, upon which the art of accompaniment, 



