“Thoughts that voluntary move
      Harmonious numbers.”

As there are certain sounds that excite certain movements, and the song and dance go together, so there are, no doubt, certain thoughts that lead to certain tones of voice, or modulations of sound, and change “the words of Mercury into the songs of Apollo.”  There is a striking instance of this adaptation of the movement of sound and rhythm to the subject, in Spenser’s description of the Satyrs accompanying Una to the cave of Sylvanus.

“So from the ground she fearless doth arise
And walketh forth without suspect of crime. 
They, all as glad as birds of joyous prime,
Thence lead her forth, about her dancing round,
Shouting and singing all a shepherd’s rhyme;
And with green branches strewing all the ground,
Do worship her as queen with olive garland crown’d.

And all the way their merry pipes they sound,
That all the woods and doubled echoes ring;
And with their horned feet do wear the ground,
Leaping like wanton kids in pleasant spring;
So towards old Sylvanus they her bring,
Who with the noise awaked, cometh out.”
Faery Queen, b. i. c. vi.

On the contrary, there is nothing either musical or natural in the ordinary construction of language.  It is a thing altogether arbitrary and conventional.  Neither in the sounds themselves, which are the voluntary signs of certain ideas, nor in their grammatical arrangements in common speech, is there any principle of natural imitation, or correspondence to the individual ideas, or to the tone of feeling with which they are conveyed to others.  The jerks, the breaks, the inequalities, and harshnesses of prose, are fatal to the flow of a poetical imagination, as a jolting road or a stumbling horse disturbs the reverie of an absent man.  But poetry makes these odds all even.  It is the music of language, answering to the music of the mind, untying as it were “the secret soul of harmony.”  Wherever any object takes such a hold of the mind as to make us dwell upon it, and brood over it, melting the heart in tenderness, or kindling it to a sentiment of enthusiasm;—­ wherever a movement of imagination or passion is impressed on the mind, by which it seeks to prolong and repeat the emotion, to bring all other objects into accord with it, and to give the same movement of harmony, sustained and continuous, or gradually varied according to the occasion, to the sounds that express it—­this is poetry.  The musical in sound is the sustained and continuous; the musical in thought is the sustained and continuous also.  There is a near connection between music and deep-rooted passion.  Mad people sing.  As often as articulation passes naturally into intonation, there poetry begins.  Where one idea gives a tone and colour to others, where one feeling melts others into it, there can be no reason why the same principle should not be extended to the