I've always liked a deceptively modest little poem by William Carlos Williams called "The Banner Bearer." One sentence long, 12 lines and 32 words in its entirety, "The Banner Bearer" is a good example of the short poems that Williams wrote in the 1930s and '40s as part of his ongoing, experimental search for a new American measure.
In the rain, the lonesome
dog, idiosyn-
cratically, with each
quadribeat, throws
out the left fore-
foot beyond
the right intent, in
his stride,
on some obscure
insistence -- from bridge-
ward going
into new territory.
Rhythmically speaking, this poem has an eccentric but sure sense of pacing and motion, a sly timing, an idiosyncratic certainty. I like the way the rhythm of each individual line builds into the rhythm of each quatrain, the way the rhythm of the stanzas enlarges into the fresh, offbeat music of the poem itself. In a way, Williams uses enjambment to enact both doubt and certainty, the mind hesitant and determined. He establishes and then blocks the integrity of individual lines (each new line hesitating over and qualifying the last, somehow pushing the poem forward) until the lineation itself mirrors the dog's motion, its jerky and insistent momentum. The dog seems to me an emblem and figure of the American poet -- eccentric, lonesome, determined -- setting off into new territory. In this sense, "The Banner Bearer" is an ars poetica. It also provides a good example of what Ezra Pound called the "volts, jerks, sulks, balks, outblurts and jump-overs" of Williams's style.