Although the rhythm of Carl Sandburg's "Chicago" is irregular, it is possible to find some patterns in it.
Nearly every line in the poem begins with an accented syllable; for example:
COME and show me...
Perhaps this is meant to imitate the banging of heavy machinery.
Stanza 1, and part of Stanza 2 ("Bareheaded, / Shoveling...), use very short lines with a minimal number of syllables. Perhaps this is meant to echo the brutality of the city.
The rest of the poem uses long lines with many syllables, reflecting the complexity and diversity of experiences in the city.
All of this combines to recreate the sound of a loud, brutal, complex metropolis.
One of my favorite parts about "Chicago" by Carl Sandburg is the fact that if you turn the physical poem on it's side, it looks like a city skyline. You may think that this has nothing to do with the poem's rhythm, but I believe it does.
The first five lines grab your attention and set a tone of size and stature. Sandburg's diction, "Hog Butcher," "stormy," "brawling," "City of the Big Shoulders" are rather intimidating.
In, the second "stanza," the lines get larger, like the big skyscrapers of Chicago. Remember, that they didn't exist in 1916 when Sandburg wrote the poem, but it makes it easier to understand. The subject matter is difficult: The city is "brutal," "crooked" and "wicked" and the lines set a rhythm of speed and a sense of overwhelming presence, again, intimidating outsiders. Meanwhile, the insider, the speaker, is proud to be a part of Chicago and all the "negatives" that come with it.
Again the rhythm abruptly halts with a list of five descriptive and powerful words: "Bareheaded/Shoveling/Wrecking/Planning/ Building, breaking, rebuilding."
Finally, in the last stanza, the pace becomes overwhelming again, describing the laughter of the speaker. This serves as the final point, in which the speaker is "proud to be Hog Butcher, Tool Maker, Stacker of Wheat, Player with Railroads and Freight Handler to the Nation." The pace, rhythm and diction make the reader feel as if it is impossible not to pay attention to Chicago.