Two of Our Recent Biblio Picks

We recently picked several old books at a book sale. While the condition is only mediocre to good, we did find some interesting ones including these two. The one of the left is a first edition of an early Winston Churchill novel called Savrola. The one on the right is, I think, a first edition (of some kind) of Ben Hur. We picked several others I am curious about. Any experts out there on old books? Values? Where/how to market them? We paid about fifty cents for each book.