Two odd images open the poem: a ship in a well, and a compass in bed. Each puts something made for open distance into a closed, still place. A ship belongs to the sea and a compass to travel, yet one is stuck down a narrow shaft and the other lies under the covers. The title, "Circumscribed," points the same way, since it means drawn around, hemmed in, limited.
Then the speaker asks a plain question: what will happen to all my promise in a quiet life? The tone shifts from strange pictures to worry. The speaker seems to fear that early potential, the sense of being meant for something bigger, may fade in a settled, uneventful existence.
The mood is wistful and a little uneasy. Nothing is stated outright, so the images do the feeling for us. There's no clear answer, and the poem ends on the question, leaving the unease hanging. It could be read as regret, or as a quiet unwillingness to accept smallness.