The tide rises, the tide falls,
The twilight darkens, the curlew calls;
Along the sea-sands damp and brown
The traveller hastens toward the town,
And the tide rises, the tide falls.
Night is setting in. A  curlew  is a bird by the water that only sings at night. This line gives the feeling of the regular routine of life anew. 

The Tide Rises The Tide Falls