Read "Nephelidia" aloud and you will find it almost impossible to say what it means, which is exactly the joke. The title comes from the Greek word for clouds, and cloudiness is both the subject and the method. Lovers' looks, blushes, ghosts, heroes, God and kings drift past, but nothing stays solid long enough to grasp. Swinburne wrote it as a parody of his own manner, and what is striking is how skilfully he overdoes himself.
On the surface there is an argument of sorts. The first stanza asks a question: are the feelings thickening in our blood "looks of our lovers" shining out of some "marvel of mystic miraculous moonshine"? The second stanza answers "Nay," and the third insists "Surely no soul" is responsible. Then comes the one line that sounds like a statement: "Life is the lust of a lamp for the light that is dark till the dawn of the day when we die." Even this dissolves into paradox, since the light is dark and the dawn is death. The final stanzas widen into something like a vision of history. The skies turn "out of blue into black," dews become "the wine of the bloodshed of things," and a hoped-for day arrives when desire will run "free as a fawn" and the hunt will have "harried the kennel of kings." Judging by that last image, the poem is also borrowing the tone of political and religious defiance, but it never says what is being defied.
What holds the poem together is sound. Alliteration is piled on until it becomes absurd: "thicken and threaten with throbs through the throat," "the nick of the tick of the time." Sibilance gives a hushed, breathy line like "Sweetens the stress of suspiring suspicion that sobs in the semblance and sound of a sigh," where the s-sounds do the sighing for us. The words are chosen for how they chime, not for what they add. "Triangular tenses" and "erotic emotional exquisite error" sound weighty, but try to picture them and nothing appears. The poem shows how a reader can be carried along by music, nodding at depth that is not there.
The form adds to the effect. Each line is long and galloping, built mostly from anapaests, those da-da-DUM beats that roll forward like a wave. Lines run to six strong stresses, so you have to read them in one breath, which leaves no time to ask what you have just said. The stanzas are quatrains rhyming ABAB, and the A-rhymes are often triple rhymes, which are hard to find in English: "noonshine" with "moonshine," "agitation" with "recreation," "terror" with "error." They give a sense of virtuoso skill, and they also sound faintly comic, because the rhyme seems to steer the sentence instead of the other way around.
The imagery shows the same pattern. Colours keep shifting (pallid, pink, flushed, gaunt, green, blue, black), but they behave like moods, not descriptions. A "theatre thronged at appeal of an actor's appalled agitation" suggests melodrama, and "ghosts go aghast" is a ghost story turned into tongue-twister. Death, fear and hope all appear, but only as raw material for rhythm.
The poem matters because it works as criticism from the inside. A parody that only mocked would be easy, but this one has to reproduce the real strengths of the style it targets: the momentum, the lush vocabulary, the grand rhetorical questions. It makes the reader feel both the pleasure and the danger of that style. When sound leads and sense trails behind, poetry can slip into mist. For students it is a useful lesson in reading closely. It teaches you to ask of any ornate passage whether the music is carrying a meaning or hiding the lack of one. It is also a rare example of a poet laughing at his own habits, and that laughter is part of what makes the poem so memorable.