Jane Austen often mentions income to express the wealth of a character, but I never saw her specifically stating what Mr. Bingley or Mr. Darcy did for a living. "Trade" was as specific as she would get. What kind of trade is she referring to? Why was she so ambiguous regarding this yet frequently states figures?
Could it be the slave trade that was common during that time?
How would this affect the story? In other words how different would the story be if Austen was more specific?
Your answers will be useful and highly appreciated!