I would say that the ideal of imagist poetry which is best reflected in this poem is that poets should be able to describe ordinary objects in new ways.
1. narwhal what Aronnax thinks the monster may be (a sea unicorn)
2. Abraham Lincoln United States' government boat
3. static character does not change
4. scientist Aronnax
5. shaped like a cylinder Nautilus
6. denouement name of the resolving action after the climax
7. 20,000 Leagues Under the Sea science fiction
The billows .... sleep.
Personification is when you give a human characteristic to something, in this case, sleep