Twilight sets the scene: an old man stands by the sea as the palm trees loom over him like bats' wings, as if the darkness itself were swooping down. He presses a hand to his chest, and his heartbeat seems to match the waves breaking on the half-drowned rocks. The image makes him feel small and fragile, caught between the body's rhythm and the sea's.
With one finger he draws shapes in the warm air, and the poem calls this "a eulogy of solitude." He isn't mourning a person so much as his own aloneness, putting it into a kind of silent speech. The last three lines shift to a more personal voice. The speaker says ghosts can hear us when no one else can, and that this is a comfort. The mood is quiet, eerie and sad, but it ends with a small, strange warmth: if no living person is listening, perhaps someone unseen is.