how do i find the literary device in this poem?

Her beam on the waves,
I gazed awhile
On her cold smile
Too cold-too cold for me-\
There pass'd as a shroud
A fleecy cloud,
And i turned away to thee,
Proud Evening Star

That's not the whole poem. If you don't consider the WHOLE POEM, you'll never get it.

http://www.poetryloverspage.com/poets/poe/evenings.html

Who is "Her" referring to?
Who do you think "I" is? (And don't tell me it's Poe!!)
What images come to your mind's eye as you read THE ENTIRE POEM?

Make notes and lists. Let us know what you come up with.

To find the literary device in this poem, you can start by closely examining the language and structure of the text. Literary devices are techniques or elements that writers use to convey meaning or create a desired effect. One common literary device that often appears in poetry is symbolism, where specific words or phrases represent abstract ideas or concepts.

In the given poem, the literary device used is symbolism. The poet uses the celestial object "Evening Star" to symbolize someone or something that is more desirable than the subject described in the earlier lines. The poet compares the "cold smile" of the subject to the "beam on the waves" of the Evening Star, suggesting that the star holds greater warmth and appeal. This symbolizes the speaker's shift of attention and affection from the initial subject to the star, indicating a change in emotions or thoughts.

By recognizing the use of symbolism and analyzing the deeper meaning conveyed through the words and imagery, you can successfully identify the literary device in this poem.