There's some good pastime reading for you. Imagine being examined for promotion to Locomotive Engineer, and having to answer in longhand, a question on just about every rule in any of those rule books. And after the written exam, you would have the opportunity to answer all of those questions again, orally. And the B&OCT and IHB timetables are full of interesting special rules that apply at specific locations. They are a window into the classic era of railroad operation.
You found some good books and timetables.