"Analysis" (解析 Kaiseki?) is the 51st chapter of the Toaru Kagaku no Railgun manga series.
Baba Yoshio scoffs at Wannai Kinuho's and Awatsuki Maaya's intent at fighting for their friend. Saten Ruiko struggles to carry Kongou Mitsuko and is attacked by one of Baba's robots, but Kinuho destroys the robot using water controlled with her power. Maaya then uses her own power to make Kongou lighter so that Saten can carry her away more easily. Saten runs across a bridge and Kinuho and Maaya stop the robots from following her. Baba pretends to be frustrated but secretly thinks to himself that the Type: Mosquito robot on Kongou will let him track her down later. He is contacted by his colleague Kouzaku Mitori and turns down an offer of reinforcements, telling her to manipulate information to keep Anti-Skill from arriving any time soon. Baba then analyses the two girls' powers. His next move is to open a conversation: he claims to be looking for Misaka Mikoto's sister and asks Kinuho for the information she has on her, in exchange for a Type: Mosquito robot (needed to treat Kongou, who was incapacitated by another robot of that type). Kinuho turns down the offer and says they'll take the robot even if they must use force. Baba responds by showing them two cases, only one of which contains the Type: Mosquito, and throws one case to a Type: Great Dane which runs off. Maaya runs after it while the other Type: Great Danes keep Kinuho from following her.
Mikoto is still with Misaki's clique. An ambulance passes them and stops nearby. Mikoto sees Saten there so she runs up and discovers that the ambulance was carrying Kongou.
Meanwhile, Kinuho is still fighting against Baba's robots. Baba notes that she can no longer replenish her water supply as they're away from the lake. Kinuho tries attacking Baba but a robot intercepts the attack, splashing the water on the ground. This lets Baba realize that Kinuho can't control water once it's spread apart. Baba thinks that Kinuho can only control three clumps of water at once and is losing some water each time she repels an attack, so she will eventually lose to him.
After following Kongou inside the hospital, Mikoto becomes quietly enraged, thinking that Misaki is willing to hurt even fellow students. She pulls the Type: Mosquito off Kongou and heads to the exit. One of Misaki's clique asks her to wait until the other clique members arrive, but Mikoto orders them to get out of her way unless they are prepared to kill her to stop her.
By order of appearance:
- Kouzaku Mitori (cameo)
- Hydro Hand - Wannai Kinuho, Level 3
- Float Dial - Awatsuki Maaya, Level 3
- Electromaster (Railgun-variant) - Misaka Mikoto, Level 5