"July 18, Part 1" (七月十八日① Shichi-gatsu Jū-hachi-nichi ①?) is the 4th chapter of the Toaru Kagaku no Railgun manga series, published on August 21, 2007. This chapter is the first part of the graviton bombing occurrences.
Kuroko is explaining to Mikoto what happened to Konori Mii and an unknown judgement officer last evening. They were evacuating everyone from a local store because of a graviton acceleration. While helping an injured person, the unknown judgement officer got severely injured from a graviton.
Kuroko also explains that the person setting these gravitons are putting them in aluminum cans. They haven't figured out who the culprit is, but Mikoto suggests that it's someone with a psychic ability. She also says that Kuroko will easily find him in the bank, but Kuroko says that there is only one person with that kind of ability and she has been in a coma for the last 8 days.
Meanwhile Saten Ruiko calls Uiharu Kazari's name and flips her skirt (something she does constantly). Saten thinks Uiharu calls her name way too formally and suggests that they get closer with each other. Saten shows Uiharu her new music tracks that she got, while a strange boy with earphones walks by. He bumps into some other fellows, and they start to beat him up. A judgement officer comes by and and the boy complains that the officer should've come sooner.
In the classroom of Sakugawa Middle School, Uiharu and Saten are learning about AIM diffusion Fields.Saten asks Uiharu if she wanted to go to the Seventh Mist and starts teasing her. The teacher overhears teir conversation and smacks their heads with a piece of paper. When they both get out of school they meet up with Mikoto. Saten drags Uiharu off somewhere else asking how she knew a student from Tokiwadai. Uiharu answers by saying she knows her inderectly from judgement and finishes off by saying that she is Misaka Mikoto, the railgun. After Uiharu and Saten praises her, Mikoto asks if can go shopping with them, and they agree.
The same strange boy seems to have gotten in trouble again. Some delinquents start asking him for money. After he refuses he gets beat up again. He starts asking what the judgment officers are doing, when they're supposed to be looking after people.
Saten starts asking if there is such a thing called a "Level Upper". She starts thinking if it was real and if she would use it. Uiharu reassures her by saying that those are just rumors people create on the web. Mikoto takes this into consideration, that this might be why they couldn't track down a suspect from the graviton cases.
Kuroko is exhausted in her judgement office room looking for clues of the graviton case. She finds out that just in the graviton case, nine judgement officers were hurt.
The strange boy decides that he's not going to wait for judgement officers anymore, and that he's going to take matters in his own hands. He is seen going inside the Seventh Mist with a stuffed frog in his hand.
- This is a manga original story, thus this is not adapted from a light novel.
- Electromaster (Railgun-variant) - Misaka Mikoto (officially introduced in cover)
- Synchrotron - Kushiro Katabira, Kaitabi Hatsuya
- The Judgment officer and the girl he saves reappear in Chapter 31, Chapter 69, and cover of Toaru Kagaku no Railgun Manga Volume 12. In Chapter 31, the officer and the girl are in casual wear and blushing, hinting that they're on a date. In Chapter 69, they're taking part in the bonfire dance together. In cover of Volume 12, they are on a date.
- Uiharu mentions that Mikoto railguned the bank robbers from Chapter 1
- Saten's music player looks similar in design to an iPod Nano 2nd generation.
- What did Kaitabi Hatsuya mean when he was going to take matters in his own hands?
- Saten Ruiko: U~~i~~haru, Good Morning!! - to Uiharu flipping her skirt