The opening line makes a promise that the next two lines seem to break. There is "a voice, not understood by all," and we expect a message, perhaps even words. What arrives is a roar. The voice turns out to be the sound of ice splitting, wind hitting trees, and water falling. These five lines were cut from Shelley's "Mont Blanc" (the title tells us so), and they break off mid-sentence, but they still hold a complete idea. Nature speaks in force rather than language, and some people can learn to listen.
The form is steady and a little loose at once. The lines run in roughly iambic pentameter, the usual rhythm of English blank and rhymed verse, so "There is a voice, not understood by all" has an easy, almost conversational beat. The rhymes are less tidy. "All" and "call" pair up across a line, but "roar" has to wait until the very last word, "pour," for its answer. In a poem about mountains, that delayed rhyme feels like an echo coming back from far across a valley. "Blast" has no partner in the fragment at all, and the missing lines that would have supplied one add to the sense of something cut short.
Shelley also lets the metre act out the action. Line four opens with "Plunging," stressed on the first syllable, so the line drops off the edge instead of climbing into its rhythm like the lines around it. The verbs and nouns pile up in the same direction: *plunging*, *descending*, *pour*. Every movement in the passage is downward, as if gravity itself were the speaker.
The word choices reward a slower look. The "desert-caves" are not sandy. "Desert" here means deserted, empty of people, which suggests that the voice comes from a place with no human audience. Then there is the "rent ice-cliff," where "rent" means torn open, a harsh, violent little word. It is followed by the oddly gentle phrase "which the sunbeams call." The sun does not melt or break the cliff. It *calls* it, and the ice obeys. A destructive event is described as a summons, so the beauty of light and the violence of the avalanche belong to one act. The passage also gathers three forms of matter into a single chorus: ice, air ("the blast"), and water ("the torrents"). The pines stand in the middle of it, the only living things named, and the wind simply descends on them.
The syntax carries the idea as much as the images do. "It is the roar… it is the blast…" repeats like a definition being built from examples, with the dashes keeping the list moving. Shelley never says what the voice *means*. He only says what it *is*, and each item is a sound without a word in it. That leaves the opening claim, "not understood by all," slightly mysterious. If the voice is only noise, understanding it must mean something other than decoding it. The poem suggests it takes a particular attentiveness, a willingness to hear a meaning in the sheer fact of power. The final ellipsis after "pour" leaves the torrents still running, with no full stop to contain them.
That phrase "not understood by all" is not a one-off. The finished "Mont Blanc" closes by addressing the mountain and saying its voice is "not understood / By all," but that the wise, great and good can interpret or deeply feel it. So the cancelled lines seem to be an early or alternative route to a thought Shelley clearly cared about. Why he cut them we can only guess. Perhaps the passage was too literal or too compressed, but that remains speculation.
What makes the fragment worth reading is how much it does in so few lines. It shows a poet turning landscape into speech without pretending the landscape talks like a person. It also puts the reader in the position of the listener the poem describes. We are given the roar, the blast and the pour, and we have to decide whether we are among those who understand it.