"July 24, Part 3" (七月二十四日③ Shichi-gatsu Ni-jū-yokka ③?) is the thirteenth chapter of the Toaru Kagaku no Railgun manga series, released on March 21, 2008.
Shirai Kuroko looks up Kiyama Harumi's history: she used to be an elementary school teacher, but resigned after a student lost consciousness during an experiment to develop esper abilities.
Harumi and Misaka Mikoto fight on top of a highway. Mikoto expresses her surprise at Harumi being able to use Dual Skill. Harumi corrects her, saying that her power works through a different method and would more accurately be called Multi-Skill. They exchange attacks, with Harumi showing that she can use multiple abilities at once. Mikoto asks Harumi to stop, to which Harumi replies that she plans to release everyone once she has fulfilled her goal - she won't sacrifice anybody. Mikoto refuses to believe this due to all the people Harumi has involved in her plan, claiming that any research that requires going to such lengths can't be for a good cause. Harumi calls her naive, pointing out that Academy City is hiding something important in its esper development program. She throws a can and detonates it with graviton acceleration, but Mikoto is able to shield herself since she recognizes this ability. Harumi then throws an entire binful of cans, forcing Mikoto to intercept them with electricity. However, this is only a diversion, allowing Harumi to secretly attack Mikoto from behind with another can. The resulting explosion appears to incapacitate Mikoto and bury her. Harumi approaches her, commenting that a Level 5 wasn't that big of a deal.
- Edasaki Banri (cameo)
No new locations were introduced during this chapter.