Withering Hieghts #3

So Heathcliff has disapeared and Cathrine Linton is now with her fiance Edgar. A couple 3 years pass and then he turns up out of know where. They chat and he is staying at the old wuthering heights with his brothers. Now in the begging of the book it said that Heathcliff owns Withering Heights and is very rich. I don't know how he got rich because when he left he was very poor. He didn't take anything with him so he didn't have any money. Now he's back and will never be the same aperently.