I do not know anything more about the "Old Green Bible"--It was passed on to me from James Herbert Black of San Antonio, who died 15 Nov 2010. I have researched the Greens and Blacks for several years, and have not found anyone who knows anything about the original Bible's existance. Could be that one of the Hortons has knowwledge of it...
BTW, I live near Spring Texas--just north of Houston. I don't manage doing genealogy on the phone very well--I have to have my computer running to keep things straight. I am glad to share what I have learned about the family, however.
I'll send my regular email address separately.