It is dark because Barnardo has trouble seeing the other guard.
This scene takes place at midnight and it is so dark Barnardo cannot see the other guard. Barnardo shows up for his shift, but he can't clearly make out who Francisco is. Francisco has the same problem because instead of answering Barnardo he tells him to identify himself first. They get it figured out and Barnardo begins his shift.
It is said that it is based on the Civil War.
When it says the whole world is quiet could mean that theres either no one is around or nobody is listening.
Voice meaning maybe this is there time to speak up and talk.
Answer: I think it means the toxins the ocean releases from the bottom
Explanation:
