Idk, what do you mean? Do you want to use it as a simile in a sentence? If you answer, i'll be very happy to help you out! :)
Answer:
To explain Thoreau's view that we have a responsibility to act
I read the book like 4 years ago, so I don't quite remember, but I think it measles, and you can cure that with a vaccine... I hope I'm right, very sorry if im not.
Rupt- is what you are looking for. :)
The phrase that indicated a lost in thought feel is the "Midnight shakes the memory". It means that his train of thought is going double time in the dark or at night.