The Tide Rises, the Tide Falls
Curlew timing
Curlews are wading birds that feed at low tide and call at dusk. This isn't decorative—it tells you the tide is going out as night falls.
Personification shift
The waves suddenly have hands. This is the only moment in the poem where nature becomes human—right when it erases human traces.
Efface
Not 'erase' or 'wash away'—'efface' means to make something lose its face or identity. The traveler's existence is being unmade.
Hostler
A hostler (or ostler) is a stable worker who tends horses at an inn. The traveler's horse is waiting, but he'll never ride it again.
Nevermore
Written 1879, forty years after Poe's 'The Raven.' Longfellow knew exactly what word he was using here.