I have 2 glass negatives 5x7 by Lee Moorhouse of Cayuse twins dated 1898 with Lee Moorhouse's name on it. They are in pretty good condition. What are they worth, and what should I do with them?

It is hard to say anything about worth as what you have may be a reproduction. The ones you describe are the ones he is most famous for. You might try contacting this entity and find out more information as to what you really have.

Lee Moorhouse photographs | University of Oregon Libraries (http://library.uoregon.edu/speccoll/photo/Pendleton/fmoorhouse.html)