The requisites of form are rhythm and metre. The accidents of form are rhyme (consonance), assonance, stanza, alliteration, onomatopœia, etc., etc.
Rhythm has to do with the kind of feet in a line, while metre has to do with the number of feet in a line. Rhythm corresponds with the regular rise and fall of the waves of the sea, each wave-length being counted a poetic foot. Metre corresponds with the swell of the sea, composed of several successive waves. Thus metre is, after all, a kind of rhythm,—the larger ebb and flow of rhythm.
The accidents of form, such as rhyme, stanza, alliteration, etc., we find worthily and advantageously used in much true poetry, as well as worthlessly used in the tawdry puppet-shows of mere mechanicians;—those persons who, having nothing to say, yet attempting to say something, mistake rhyme for sense, a tickling jingle for meaning, their desire to create for the creative power. They do not rightly read nor well heed the trite epigrammatic precept, “When you have nothing to say, say it.”
But these accidents of form, I say, are sometimes material aids to the thought; indeed, always are when used not for their own sakes but for the meaning’s sake. Notwithstanding this fact, many of our greatest poems, such as Paradise Lost and others on the epic order, as well as many not epic, lack these accidents either wholly or in part.
On the other hand, rhythm and metre are found in all poetic forms, and are the only two elements of the form of poetry that are thus found. Hence, rhythm and metre are not only essentials but they are the only essentials of form, and constitute the complete body in which the spirit of poetry naturally and inevitably clothes itself. They are, therefore, just as necessary to poetry in its concrete or visible forms as the spirit is.
But since rhythm and metre are thus essential to a poem, it is the common custom to call anything poetry that has this external appearance of the poetic.
This is a misapplication of terms. There is so much trash masquerading in the poetic garb that this misapplication inevitably throws ridicule upon true poetry.
Rhythm, when carried to excess and when used not for the meaning’s sake, the feeling’s sake, but for the rhythm’s sake alone, becomes simply jingle; quite invariably a rhyming jingle at that.
Metre, in company with rhythm and rhyme, is often diverted from its true purpose and used solely to jiggle some fact or some epigram into the memory, as illustrated by “Thirty days,” etc., and by all other didactic metrical arrangements, as mentioned farther on.
But rhymes and jingles and metrical arrangements are not poetry. They are simply members of the form, the dancing legs and arms of the body, sometimes possessed of life with an indwelling guiding spirit, and sometimes whittled out of wood and set in motion by an inspiring string. These senseless puppets, or jumping-jacks, sometimes, indeed often, tickle the mob by their lively antics; but the great final judgment of humanity relegates them to the rubbish-heap and forgets their ephemeral and unlovely existence.