Final answer:
The men around the fire were able to engage in open and unrestricted conversation, displaying their intellectual curiosity and ability to communicate effectively.
Step-by-step explanation:
The significance of the men around the fire who 'talked of everything, there was nothing they could not talk about' is that they were able to engage in open and unrestricted conversation. They possessed a breadth of knowledge and were comfortable discussing a wide range of topics. This demonstrates their intellectual curiosity, social connection, and ability to communicate effectively.