How did Ben become the owner of the Ponderosa?

[Rika]

Ben had no money, he had nothing when he came to the West. But he became the owner of big ranch. How did he do that? Was anything said about this in the show?

I don't know history of the Old West and I wonder how it was possible.

I tried to find some information about this on forum but I didn't.
If somewhere there is the same topic maybe you could help me to find it please.