Continuity mistake: Monty (Brendan Fraser) was listening to Simon (Joe Pesci) tell stories about his bag of stones while standing on crutches. Simon offers to carry Monty's books, and Monty hands him the books, keeping his backpack on. In the next scene, they are crossing the bridge and Simon is empty-handed and the backpack is missing as well. (00:37:45)
Continuity mistake: When Monte puts the book "Leaves of Grass" on the table in the library at the end, it shows a close up of the book. Next, it pans out and the book is no longer on the table.