‘Acquainted with the Night’ is a poem by Robert Frost (1874-1963), published in 1928. One of Frost’s most popular short poems, it is slightly unusual in his oeuvre in focusing on the urban rather than rural world of many of his other famous poems. You can read ‘Acquainted with the Night’ here before proceeding to our analysis of the poem below.
To summarise: ‘Acquainted with the Night’ is a lyric poem in which the speaker (who may or may not be Frost himself) tells us that he has been one of those people ‘acquainted with the night’, who has walked outside, and home again, in the rain. He has walked far, out to the farthest edges of the city, where the city lights stop and he is plunged into a deeper darkness. There is a suggestion of pathetic fallacy here: ‘night’ and ‘rain’ are both suggestive of gloomy or melancholic emotional states, and there’s a possibility that Frost’s speaker wants us to think beyond the literal and into the metaphorical: he is no stranger to dark thoughts and to sadness.
Indeed, such an analysis of the speaker’s meaning seems well-founded when he tells us, in the fourth line, he has ‘looked down the saddest city lane’ (where ‘I have looked down’ glimmers, momentarily, with the secondary meaning of looking down in the mouth, or looking depressed). Seeing a night-watchman out on his patrol, or ‘beat’, the speaker has avoided his eye contact, perhaps because he suspects that if their eyes meet the watchman will ask him what brings him out so late. The speaker would rather not say.
In the third stanza, the speaker tells us he has stopped walking until the echoes of his footsteps cease, and he hears an ‘interrupted cry’ carry through the night air from another street. But the cry is not meant for him (either someone calling him back or bidding him farewell). A tall clock (perhaps the town clock, in a clock tower, but probably the moon, given the word ‘luminary’, i.e. emitting light) high above him gives him the time, which is ‘neither wrong nor right’. Perhaps this is 
because, it being night time, there is no right or wrong time for the speaker: time has largely lost its meaning, in terms of hours and minutes. The poem concludes with the speaker repeating that first line: he is (or has been) ‘one acquainted with the night’.
‘Acquainted with the Night’ has been interpreted as a poem about loneliness, but this seems to be a reductive or even misguided analysis: the speaker appears to revel in his solitariness rather than feeling the lack of other human company, and notably, the one person he ‘meets’ in the poem, the watchman, he goes out of his way to avoid speaking to.
One of the problems in interpreting the meaning of the poem is that Frost’s speaker refuses to tell us how he feels about his solitary wandering through the night: he is, to borrow a phrase from the poem, ‘unwilling to explain’. Does he crave human company, does he wish that he had someone to call him back home? Ultimately, as with that interrupted cry in the poem, there is no answer.
Although it doesn’t necessarily strike us as one, ‘Acquainted with the Night’ is an example of the sonnet form: fourteen lines written in iambic pentameter. Or at least, ‘Acquainted with the Night’ appears to be a sonnet, since it has fourteen lines, is rhymed, and is written in (fairly regular) iambic pentameter.
However, the rhyme scheme does not match the rhyme scheme for any established sonnet. The poem is rhymed aba bcb cdc dad aa. And Frost’s decision to divide the poem into four tercets and a concluding couplet further disguises the poem’s links with the sonnet.
In fact, ‘Acquainted with the Night’ is not really a sonnet at all: the fact that it has fourteen lines and concludes, as the English or Shakespearean sonnet does, with a rhyming couplet is where the similarities end. Instead, the poem is written in the Italian verse form known as terza rima, a three-line stanza form using what’s known as ‘chain rhyme’, where the middle line of each three-line stanza becomes the outer rhymes for the subsequent stanza (so ‘rain’, the middle line of Frost’s first stanza, gives us ‘lane’ and ‘explain’ in the first and third lines of the following stanza; ‘beat’ then gives us ‘feet’ and ‘street’; and so on).
However, Frost’s decision to conclude this pattern of chain rhyme by bringing the rhymes full-circle – i.e. back to ‘night’ rhyme that began the poem – so that the whole thing comes to fourteen lines is certainly interesting, and is perhaps meant to call to mind the sonnet form.
Terza rima was first used by the medieval Italian poet Dante Alighieri (1265-1321), who used the three-line stanza form for his religious epic, the Divine Comedy. Dante also wrote sonnets, so we might surmise (though we cannot know what Frost’s intentions were for sure) that Frost was setting out, with ‘Acquainted with the Night’, to write a ‘Dantean’ poem, whose form echoes those associated with Dante.
And thematically, too, there is something Dantean about ‘Acquainted with the Night’, with the dark city doubling up as a land of spiritual darkness, or ‘city of dreadful night’. This is not to say that the poem is religious – it is decidedly secular – but Frost’s choice of verse forms summons the possibility that he wishes to offer a secular, modern take on Dante’s vision of the Inferno.