The Bolt Book can be found in Castle A at the Clock Tower in the metal ball race room. Unlike Castle B the race will be alot harder, there will be spikes, Bone Pillars in stacks of 4, wooden platforms to drop down instead of falling, and Arabaki. The best way to get ahead of the metal ball is to use the cross/wind book spell. You can dash and slide while the flying crosses protect you. Use slide for the bone pillars.. If you fail to beat the ball, exit the room and try again.