What is the name of the book I cannot help you if I do not know the book.
Answer:
It means to favor one arty over the other.
Explanation:
The narrator goes to visit Usher, because his friend Roderick sent him a letter requesting his company. Roderick wrote he was feeling physically and emotionally ill so the narrator rushes to see him.
And how you are this is why in the end of the string is telling us a signal of friendship