Gladness is a hard mood to write about without sounding smug or sugary. William Allingham sidesteps the problem by opening with a plain, almost spoken sentence: "I'm glad I am alive." It has no ornament, just a person stopping on a fine morning and saying so. The rest of the poem tries to account for that feeling, and the answer it finds is that joy, once it is big enough, cannot stay inside one person. It spills into other people's work, then into the sky, and finally into a song the speaker wishes he could sing.
The first eight lines are pure looking. The day is "like a heart with nothing to conceal." The image turns a cloudless sky into a kind of openness of character, and the rhyme on "reveal" a few lines later seems to confirm it: nothing hidden, everything on show. The list of sights, "Brairds, hedges, shadows; mountains," is chopped up by semicolons, so the eye hops from one thing to the next as if there were too much to take in at once. (A braird is a field of newly sprouted crops, so even the humblest details are signs of spring.) The colours are soft: "blue-grey," "soft sapphire," leaves "scarcely trembling." Against them the sea arrives as a "great floor of polished steel," a hard, bright, metallic image that suggests a surface so still it could be walked across. Even the phrase "full deliciousness" borrows from taste to describe what the eyes see, as though the day were something to be eaten as well as looked at.
The form is a sonnet, and the break after line eight matters. In the octave the rhymes run ABABBAAB, so the sounds of "feel," "conceal," "reveal" and "steel" return four times. This gives the descriptive section a ringing sameness, like the unclouded day itself. The sestet loosens the pattern. "Door" and "soar" form a little couplet in the middle, and "net" is answered only by the softer, near-rhyme of "laureate." The last line stretches to a full six beats, "Joy culminates in song! If such a song were mine!", so the poem seems to run over its own edge.
The grammar changes too. In the octave the speaker only observes, but in the sestet he acts: he stoops, tends, sits, plies. He seems to slip into the lives of a fisherman hauling a net, a herdsman driving "milky kine" uphill, and someone spinning at a cottage door. The poem never says whether he is really doing these things or imagining himself into them, and that uncertainty is part of its charm. The work is not prettified. The gunwale is "black," the path is "rough," the thread is "diligent." But everything happens "in sunshine," so joy here does not deny labour but lights it. Then comes the dash after "take wings and soar," and the sentence takes off from the ground and breaks off in mid-air.
What interrupts it is a new voice: "O hark." The "season's laureate" is presumably a bird. The idea of soaring and the word "song" suggest a lark, though the poem never names it. Calling a bird the laureate is playful, since it makes spring a kingdom with an official poet, and it quietly demotes the human writer. The last line, "If such a song were mine!", is wistful. The poem we have just read is itself a song, yet its speaker feels it falls short of the spontaneous music overhead.
That ending is what makes the poem worth reading. Many poems celebrate a beautiful day, but this one traces how happiness moves outward, from seeing to doing, from doing to flying, from flying to singing, and then admits that the poet's own art can only reach after the bird's. It finishes with longing rather than boasting, and the humility makes the opening claim, "I'm glad I am alive," easier to believe.