A walker stops a little girl and asks where she is going. That is the entire event of Clare's "Impromptu", and the title admits as much: this is a feeling caught on the spur of the moment, still fresh from an encounter "to-day". Yet in sixteen lines the poem moves from friendly country chat to a quiet confession of loss.
The first stanza gives most of its room to the child. The speaker's question takes up a line and a half, and her answer fills the rest. We see her through one small gesture, as she "pushed her bonnet up and smiled", and then hear her in a single run of speech. Her knowledge of spring is secondhand and delighted: "Folks tell me that the May's in flower". "May" here is the hawthorn blossom, and she takes the news on trust, as children do. The hyphenated "cowslip-peeps" is the kind of homely, specific word that makes the scene feel overheard rather than invented, and "peeps" suggests tiny flowers looking out of the grass. Her ambition is modest: "this little basket full". The word "little" appeared in the first line to describe the child, and its return here quietly matches her size to her wish. The errand is both work and play, a chore she is thrilled to do.
The second stanza turns on a repetition. "And thou'st got leave to spend an hour!" is her own phrase handed back, and the dashes make it sound like a thought interrupting the speaker mid-breath. He fixes on two words she barely noticed, "leave" and "hour". Even her freedom is lent, granted by someone else and measured out in time. Then comes the abruptness of "She was gone", a short statement that ends the meeting as quickly as a real one would end. The speaker's heart goes on talking to her anyway, now with the intimate "thou", and it adjusts her news: "the thorn's in flower". Swapping "May" for "thorn" may be only a change of name for the same blossom, but the judging-by-the-sound effect is of a small prick inside the pleasant word. The phrase "childhood's bliss is urging on" is ambiguous in a useful way. It can mean that happiness is pushing the girl forward, or that childhood itself is hurrying her along and will not wait.
The sigh arrives in the last four lines. "Ah, happy child! thou mak'st me sigh" is the poem's one open exclamation, and the speaker immediately reins himself in with a conditional: "Would nature with the boon comply". Nature is imagined as a power that could grant a favour, but he does not expect it to. The inverted phrase "This once as happy heart of mine" lets "once" carry the whole weight of what has been lost. The final line, "How gladly would I change for thine", offers a swap of hearts, which is impossible, and the impossibility is the point. Notice, too, that he never says why he is unhappy. The poem leaves the reason blank and lets the contrast do the work.
The form supports this plainness. Both stanzas are eight lines of mostly iambic tetrameter, rhymed ABABCDCD, an easy, speech-like beat close to a ballad's. Almost every word is a single syllable, so nothing sounds decorated. The rhymes of "flower" and "hour" appear in both stanzas, closing lines in the first and opening the rhyme pairs in the second. The sounds echo the way the speaker's heart echoes the child.
What makes "Impromptu" worth reading is how much it holds with so little. There is no grand metaphor, no lecture on time. It has a bonnet, a basket, a few flowers and a sigh, and still it shows the adult's longing for a happiness that is unselfconscious and does not look at the clock. The envy is gentle rather than bitter, and the girl, who has no idea she has caused it, skips off to fill her basket.