The speaker of Walt Whitman’s “I Hear America Singing” metaphorically describes the laboring people he names with a music metaphor: he claims that he hears them singing, which merely means that he sees them cheerfully and skillfully working.
The poem consists of ten lines that sprawl and spill into the next line without actually becoming a new line. The typist must break the sprawling lines and let them form what looks like a new line or else in some cases they would run off of the page. That is Whitman’s free verse style.
The speaker begins by claiming that he hears America singing, and the songs are all different: “I hear America singing, the varied carols I hear.” He refers to the songs as carols, which suggests that these are not just ordinary songs, but that they are joyous and offer praise.
The speaker admires the many workers he encounters, and they all seem quite happy to him. His optimism, no doubt, spills over onto the people he observes.
Then, the speaker begins to catalogue the various laborers he hears “singing”: he first hears the mechanic, and each mechanic is working in his own special way, a way which the speaker qualifies as “blithe and strong.”
Next, he names the carpenter whose song includes the measuring of planks and beams. The mason sings as he gets ready for work and as he gets ready to leave work. The boatman sings about the things that he owns in his boat, and the deckhand sings on the deck of the steamboat. The shoemaker sings on his bench, and the hat maker sings as he stands.
Next, we hear the wood-cutter singing and the farmer plowing his field morning, noon, and as the sun goes down. Then the mother is singing a “delicious” song, as does the young wife as she works, and the girl, possible a maid, as she does the sewing and washing.
They all sing unique songs, that is, they all work in ways that only each on can perform individually. They are not interchangeable, but unique individuals deserving affection and respect, and the speaker demands that respect for each of them.
As much as the speaker respects and shows abiding affection for all the glorious labors going through their day, performing their unique tasks as only each one individually can perform them, he becomes positively giddy at the thought of night time and the young revelers enjoying their time of fellowship: “At night, the party of young fellows, robust, friendly, / Singing, with open mouths, their strong melodious songs.”
He says the day has what belongs to the day, but at night these songs become utterly literal, and the singing is hearty and the friendship harmonious, producing the same sweet melody as the most beautiful song.