The tone of the story is happy and sad. The people are cheering the crew on because the civil war is ended, but are also sad because Abraham is dead.
The Imagery the author uses is he rephrases many times that "O the bleeding drops of red". He is referring as Abraham is dead and drops of blood are coming out of him. The five senses are sight, hear, taste, smell, and touch.
The word choice the author uses is O Captain, blood, heart!, dead, fallen, and O Heart!
Each eight- line stanza is split into two distinct parts. The first four lines are long and praise Lincoln's achievements. The last four lines are abut his death and show descriptions of his death.
The theme of the poem is that the captain ( Abraham Lincoln) is no more to enjoy the victory. Even though the theme runs throughout the story as his death, it is also excitement the war is over.
This poem is an extended metaphor that compares two things. It compare the unlike things for the United States after the Civil War, and Abraham Lincoln's assassination