I think the best answer is C or D. Don't take it from me though.
Answer:
He refers by 'pulse' the way you can check the state about something that is not visible at once, like when you check somebody's heart condition just by checking his pulse or heartbeat. Even though he lived in the continent and he could check the state of things as a journalist, he could imagine or make an idea for himself about what was the state of things in places he couldn't see or visit by himself. Then, this idea would come from the people who used railroads which crossed the continent by then. It is also a way to describe media in his times because he could know about something that was happening somewhere else through the fastest transportation mean in his time. As public transportation means, people who used railroads also brought news from they were coming from, so locals could know the whereabouts from a distant place that they could know or check by themselves.
Explanation:
I used the term 'pulse' to explain what does Whitman mean on this statement.
The answer is ‘fashions changed, and the use of furs in fashion ended’
Because of the river gave them advantage to spread and conquer.
Step by step:
5) C
6) B
would be the answers for the two questions hope it helped