The poem sets a scene in a coffee house, where conversation is imagined as something huge and wild: "a great wind." From there the images pile up in a slightly dreamlike way. Trees blow down, letters arrive from the forest, and a thousand oaks walk to Brampton, which turns out to be happening "in the news." The strange, almost fairy-tale picture of walking oaks seems to be how gossip and headlines feel when they sweep through a room, uprooting everything solid and turning it into story.
The speaker sounds amused but a little wary. Calling these tales "good" suggests real enjoyment, yet the last line calls them "thieves / that rob us of time," so the pleasure comes with a cost. The title's warning about loose lips adds to this, hinting that careless talk has consequences. The mood is playful and slightly uneasy: it's fun to be swept along by talk, but you may look up and find the hours gone.