Wailing of reed-bird (symbol)
Within the context of the poem, the wailing of the reed-bird that will not "waken" the reader could function as a symbol of aliveness, suffering, visceral sensation, and cognizance—the very state of being that the speaker imagines the reader longs to escape.
The roll of the full tide (allegory)
The speaker's vision that the reader longs to be covered by the tide may operate as an allegorical statement about how people long to feel numb at times, despite the vibrancy and value of life. The litany of lovely, visceral images and sensations in the previous stanzas illuminates how, according to the speaker, even such evocative, stirring realities do not match the longing for oblivion. The tide as an allegory for oblivion is apt in that water is a common symbol of the unconscious mind, and submersion in water will literally make one lose consciousness.