What are poetic devices are used in the poem "David" by Earle Birney?

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huntress eNotes educator| Certified Educator

It is in unrhymed iambic pentameter--making it blank verse--so it has specific meter (or pattern of beats). This is not to be confused with rhythm, which is the actual form those beats take (think of it like this: if climate is what you expect and weather is what you get, "meter" is the climate and "rhythm" is the weather). The entire poem is in quatrain stanza--stanzas (the poetic version of paragraphs) of four lines each. 

The poem is rife with imagery: "sunalive weekends" (3), bacon "strips festooned / On a poplar prong" (12-13), and a glittering "alien prairie" (20). 

As well, Birney uses simile (they "won" the snow of the slopes above the timberline "like fire in the sunlight" (16-17) and the "peak was upthrust / Like a fist..." (17-8), and its more muscular big brother metaphor (the "dawn was a floating / Of mists" (15-6)). 

He loves personification, as well: the sun has "retreats" (8), the Mount Gleam has "shoulders" (11), and the "pines thrust at the stars" (15). There is hyperbole: they spend an "endless hour in the sun" (31) and "valleys the moon could be rolled in (19); synesthesia: they "feast" on the sight before them (36)--a feat actually impossible to do with one's eyes; and enjambment as well as end-stopped lines. Lines 37-40 are a good example of how both are employed: 

By the fading shreds of the shattered stormcloud. Lingering
There it was David who spied to the south, remote,
And unmapped, a sunlit spire on Sawback, an overhang
Crooked like a talon. David named it the Finger.
Lines 37-40 are enjambed, meaning they are read without pause, as a complete sentence. Line 40 is end-stopped, forcing additional pause and emphasis. We are meant to focus for a moment upon "the Finger." 
The poem is both an elegy--a poem written to lament the dead--and a bildungsroman, a text about a character's coming-of-age. 
The observation of a goat's bones in lines 41-44 and his realization that "that was the first I knew that a goat could slip" is foreshadowing. David himself seems to be a mountain goat. 
In line 93, Birney uses caesura to great effect: "Then I turned to look north / At the glistening wedge of giant Assiniboine, heedless / Of handhold. And one foot gave. I swayed and shouted" (91-93). Note that the lines flow easily, with enjambment even, until line 93, where we are jolted to stop twice in one line. The shortness of phrases signal excitement and tragedy. 
That should be enough to get you started, although it's far from all the poetic devices in the poem. I suggest you Google a comprehensive list of poetic devices and see how many you can find in Birney's poem. :)