in Music, a succession of sounds ranged in Melody, such a manner, according to the laws of rhythm and modulation, that it forms a sentiment agreeable to the ear. Vocal melody is called singing; and that which is performed upon instruments has been termed symphonic melody.

The idea of rhythm necessarily enters into that of melody. An air is not an air but in proportion as the laws of measure and quantity are observed. The same succession of sounds is susceptible of as many different characters, as many different kinds of melody, as the various ways by which its emphatic notes, and the quantities of those which intervene, may be diversified; and the change in duration of the notes alone, may disguise that very succession in such a manner that it cannot be known. Thus, melody in itself is nothing; it is the rhythm or measure which determines it, and there can be no air without time. If then we abstract measure from both, we cannot compare melody with harmony; for to the former it is essential, but not at all to the latter.

Melody, according to the manner in which it is considered, has a relation to two different principles. When regarded only as agreeable to the proportions of sound and the rules of modulation, it has its principle in harmony; since it is an harmonical analysis, which exhibits the different gradations of the scale, the chords peculiar to each mode, and the laws of modulation, which are the sole elements that compose an air. According to this principle, the whole power of melody is limited to that of pleasing the ear by agreeable sounds, as the eye may be pleased by an agreeable assemblage of suitable colours. But when considered as an imitative art, by which we may affect the mind with various images, excite different emotions in the heart, inflame or soothe the passions, and produce different effects upon our moral faculties, which cannot be produced by the influence of external sense alone, we must explore another principle for melody; for in our whole internal frame there appears to be no power upon which either harmony alone, or its necessary results, can seize, to affect us in such a manner.

What, then, is the second principle? It is as much founded on nature as the first; but, in order to discover its foundation in nature, it will require a more accurate though simple observation, and a more exquisite degree of sensibility in the observer. This principle is the same which varies the tone of the voice, when we speak, according as we are interested in what we say, and according to the different emotions which we feel in expressing it. It is the accent of languages which determines the melody of every nation; it is the accent which leads us to employ the emphasis of speaking whilst we sing, and to speak with more or less energy according as the language which we use is more or less accented. That language the accents of which are the most sensible, ought to produce the most passionate and lively melody; that which has little accentuation, or none at all, can only produce a cold and languid melody, without character and without expression. These are the true principles. In proportion as we depart from them, when we speak of the power of music upon the human heart, we shall become unintelligible to ourselves and others; our words will be without meaning.

If music does not impress the soul with images except by melody, if it thence obtains its whole power, it must follow, that all musical sounds which are not pleasing by themselves alone, however agreeable to harmony they may be, do not form an imitative music; and, being incapable, even with the most beautiful chords, either of presenting the images of things, or exciting the finer feelings, very soon cloy the ear, and leave always the heart in cold indifference. It follows likewise, that notwithstanding the parts which harmony has introduced, and which the actual taste of music so wantonly abuses, wherever two different melodies are heard at the same time, they counteract each other, and destroy the effects of both, however beautiful each may be when performed alone. From this it may be judged with what degree of taste the French composers have introduced into their operas the miserable practice of accompanying one air with another, as well in singing, as in instrumental performances.

But the causes by which national melody is diversified and characterized, are more profound and permanent than the mere accentuation of language. This indeed may have great influence in determining the nature of the rhythm, and the place of emphatic notes, but very little in regulating the nature of the emphasis and expression themselves. If Rousseau's principle be true in its full extent, it must of necessity be acknowledged, that an air which was never set or intended for words, however melodious, cannot be imitative; that what is imitative in one nation cannot be so in another; and that, upon his hypothesis, the recitative, which is formed upon the mode of speaking, is the most forcible of all melodies, which is absurd. But his other observations are at once judicious and profound. Though it is impossible to exhibit the beauty and variety of harmony by playing the same melody at the same time upon different keys, admitting those keys to form amongst themselves a perfect chord, which will of consequence preserve all the subsequent notes in the same intervals; yet this perfect harmony would by no means be uniformly pleasing to the ear. We must therefore of necessity introduce less perfect chords to vary and increase the pleasure, and these chords in any complex system of music must of necessity produce dissonances. It then becomes the business of the composer to be careful that these discords may arise as naturally from, and return as naturally to, perfect harmony as possible. These causes must inevitably have the effect of varying the melody of the different parts; but still, amidst all these difficulties, the artist ought to be zealous in preserving the melody of each as homogeneous with others as possible, that the result of the whole may be in some measure uniform. Otherwise, by counteracting each other, the parts will reciprocally destroy their effects.