The form of “Ebb” is small and compact. Its miniature size might be a product of its genre or could also link to the poem’s themes. The poem is about a diminished, receding heart, so the shrunken form reflects the shrinking heart and the restricted capacity for love.

Although the poem appears nice and tidy, there are some peculiar quirks to the form because Millay indents Lines 2, 5, and 6. It’s not clear why Millay indents these lines. Yes, “died” and “tied” rhyme, but “pool” doesn’t rhyme with “died" or “tied.” Perhaps Millay indented these lines to signify remnants. The memory of the speaker’s love remains even though it died in Line 2. In Lines 5 and 6, the tide leaves behind the tiny, lukewarm pool of water. Thus, the form brings out the themes of memories and feelings that linger.

Although the poem follows no specific meter, it maintains an even sound, with the lines staying short and within a range of four to seven syllables. Millay furthers the harmonious sound because she chooses words with either one or two syllables. Similar to the speaker’s heart, Millay’s self-made meter is restricted and limited.