The speaker looks at a distant mountain peak and, in the last line, turns the comparison toward a person: you are just as unreachable. The peak is something the speaker sees again and again, yet it can never be possessed. That small gap between seeing and having is where the feeling lives.
The word "legerdemain" is the most interesting choice. It means sleight of hand, a magician's trick, and here it suggests the peak is almost a illusion. Distance makes it look close and solid, but it slips away when you try to grasp it. The speaker seems to feel the same about the "you" of the poem, someone who is visible and familiar but not truly within reach.
The mood is quiet, wistful, and a little resigned. There is longing, but no anger or drama. The short lines and the abrupt ending, "as are you," leave the reader with a gentle ache, as if the speaker has accepted the distance without ever stopping to admire it.