"The eagle of the sea!..."See in text(Text of the Poem)
The “eagle of the sea” is a metaphor for Old Ironsides. However, the eagle is also the national emblem of the United States of America; therefore, applying it as a metaphor for Old Ironsides strongly suggests that those who wish to decommission her are unpatriotic.
"And waves were white below..."See in text(Text of the Poem)
This line uses alliteration, or the repetition of consonants, in the words “waves,” “were,” and “white.” The rapid repetition of the soft “w” consonant mirrors the sound of the ocean and reinforces the poem’s steady rhythm.
"burst the cannon’s roar..."See in text(Text of the Poem)
The words “burst” and “roar” are examples of onomatopoeia, a literary device in which a word mimics the actual sound of the thing it represents. In this context, onomatopoeia reinforces the intense imagery of the scene by appealing to the reader’s senses.
"And many an eye has danced to see..."See in text(Text of the Poem)
Holmes uses uses assonance, or the repetition of vowels, in the words “And,” “many,” “an,” “has,” and “danced.” Assonance helps to create the poem’s steady rhythm. Holmes also uses synecdoche, which is the representation of a whole by one of its parts, when he refers to the ship’s onlookers as “many an eye.” In this context, Holmes uses synecdoche to suggest unity and patriotism; it is a unified nation, not a group of individuals, that proudly watches “that banner in the sky.”