Clare's "Song" is eight lines long, and almost all of it is wishing. Nowhere does the poem say where the speaker is. We learn only where the speaker would like to be, and even that is a puzzle: "I wish I was where I would be." The line loops back on itself, as if the place can't be named because it isn't really a place, only wherever the beloved is. What the speaker longs for is "love alone to dwell", to live inside love as if it were a house. "Alone" does two jobs here. It means love undisturbed and by itself, but it also carries the speaker's own solitude, which the line can't quite shake off.
The wish then grows bolder. "Was I but her or she but me" asks for more than closeness. It asks for the boundary between two people to disappear, so that neither would have to reach for the other. The grammar is worth a glance. The plain "Was" instead of the more formal "Were" keeps the line close to ordinary speech, so the longing sounds spoken rather than composed. The reward is small and homely: "Then love would all be well." The rhyme backs this up, because "dwell" and "well" chime together, as though living with someone and being well were one and the same thing.
The form is that of a simple song. Lines alternate between eight and six syllables, in a ballad-like rhythm that is easy to hum, and the rhymes run ABAB in each quatrain. The vocabulary is just as bare. Apart from "alone", "waters" and "mirrors", every word is a single syllable. That plainness makes the poem feel sincere, with no decoration to hide behind. It also makes the second stanza hit harder, because that is where things start to slip.
The first stanza imagines being with the beloved. The second drops down to a lesser hope: if the speaker can't be there, perhaps a thought can be sent. "As quick as thoughts can fly" is hopeful and fast, and the word "thoughts" is even repeated, as if the speaker were pressing it. But the sentence turns on "But", and the final image takes over: "as the winds the waters stir / The mirrors change and fly." The word order is inverted, with the verb held back until the end of the line, so the disturbance arrives almost before we understand it. Judging by the imagery, the "mirrors" are the surfaces of water that would hold a reflection, perhaps the beloved's image or the thought itself. Once the wind stirs them, they break into pieces that cannot keep a picture still. The plural is telling, since each ripple becomes a separate, shattered mirror.
The most interesting move is the rhyme. In the first quatrain the B-rhymes are two different words, "dwell" and "well". In the second, the poem rhymes "fly" with "fly". The same word comes back, but its meaning has flipped. Thoughts "fly" as an act of speed and purpose, while the mirrors "fly" as an act of escape. The very quickness the speaker hoped for turns into scattering. Because the rhyme uses the same word twice, the poem seems stuck in place, unable to move on to something new, just as the speaker cannot get across to the beloved.
The ending also withholds what the first stanza promised. Line four reached for "well", a settled, peaceful word, but the poem finishes on movement and loss. There is no answer, no reunion, and no assurance that the message arrives. The conditional mood ("would", "Was I but") never gives way to anything real.
That is what makes the poem worth reading. In eight plain lines it covers the whole path of longing: wanting to be there, wanting to be the other person, settling for sending a thought, and watching even that dissolve. The imagery is drawn from wind and water, which fits a poet whose language so often turns to the natural world. Here nature offers no comfort. It simply shows how hard it is to hold an image steady, and how easily a wish can ripple away.