This poem is set out in five stanzas, each of three lines, and each line being end-rhymed with the others in the stanza. The meter of the poem is also fairly regular: the first two lines of each stanza have five stressed syllables, while the final one has four.
The effect of the final shorter stressed line is to create a sense of fitting closure to the stanza.
This tight regularity of form is quite unusual in MacCaig’s poetry. He is often quite free in stanza length, line length, and meter, and rhyming may or may not be present; he will vary his style according to the internal requirements of a particular poem.
In this poem the tightness of structure serves to encapsulate the uniqueness of the experience, and the regularity of rhythm and rhyme matches the rhythmic quality of the rise and the fall of the sea itself, and likewise the steady pulling of the oars.
The subject of the poem is never mentioned in the body of the poem itself, instead we infer from the title what the poet's small boat collided with that day.