The Slytherins who we had infected with Bulbadox powder obviously had a terrible time, but to be honest, I didn't really enjoy their embarrassment anymore after being beaten up so badly.

Angelina and Alicia revealed that Quidditch practice had been cancelled, as the stormy weather was still ongoing.

We also found out that we would have the first meeting for the defense group at 8pm, on the seventh floor opposite the tapestry of Barnabas the Barmy being clubbed by trolls.

"That's a very oddly specific place" I said "why there? As far as I can remember there's never been anything noteworthy, it's just a stretch of corridor. I don't even think there are any classrooms or anything"

"Merlin knows" said Amy, "but if it's what Harry said there must be a good reason for it"

At 7:45, Demelza, Amy and I left the common room and headed to the seventh floor, somehow without encountering any teachers. All the members of our group had to be clever and discreet about getting there, not leaving in groups of more than three, and taking various different routes to avoid encountering any teachers or prefects. I still wasn't sure how we were going to do this without being caught. When we reached the place however, we saw that a door was set into the wall.

"I definitely don't remember this ever being here, do either of you?" I said

They shook their heads

Demelza knocked on the door and we entered. It was immediately obvious that this was the perfect place. It was a spacious room lit with flickering torches like those that illuminated the dungeons eight floors below. The walls were lined with wooden bookcases and instead of chairs there were large silk cushions on the floor. A set of shelves at the far end of the room carried a range of instruments such as Sneakoscopes, Secrecy Sensors and a large, cracked Foe-Glass.

Harry, Ron and Hermione were already there. Hermione was reading Jinxes for the Jinxed on one of the cushions.

"What is this place?" asked Amy

"Yeah, we've been past here so many times but never saw the door" added Demelza

Harry started to explain, but more people kept arriving, so he had to keep starting over. Eventually, he just decided to wait until everyone had arrived, and by 8, they had.

Harry moved across to the door and turned the key protruding from the lock; it clicked in a satisfyingly loud way and everybody fell silent, looking at him. Hermione carefully marked her page of Jinxes for the Jinxed and set the book aside.

'Well,' said Harry, slightly nervously. This is the place we've found for practice sessions, and you've - er - obviously found it OK.'

'It's fantastic!' said Cho, and several people murmured their agreement.

'It's bizarre,' said Fred, frowning around at it. 'We once hid from Filch in here, remember, George? But it was just a broom cupboard then"

"How did you find it though?" asked Matilda "you haven't explained that fully yet"

"Dobby the house elf bought Hedwig back to me after Grubbly Plank had treated her injuries. Yeah, for those of you that don't know, she was injured after Umbridge intercepted her when she tried to deliver to me" said Harry

There were grumbles and angry noises from around the room at this.

"Which has made this even more important, it's another reason why Umbridge deserves us doing this. Dobby said he knew about this room, he's bought Winky here before when she's been drunk, and it's turned into a small room with a bed and some antidotes for them. This room turns into whatever you need it to if you walk past it while thinking about what you need"

"So if I needed the toilet for example, this would turn into a bathroom?" asked Terry Boot

"Yes" said Harry "in fact, Dumbledore once found this out by accident. He was out one night, needing a bathroom, and found this room filled with chamber pots. Said so at the Yule Ball. Even he didn't know this place existed before then"

'Hey, Harry, what's this stuff?' asked Dean from the rear of the room, indicating the Sneakoscopes and the Foe-Glass.

'Dark detectors,' said Harry, stepping between the cushions to reach them. 'Basically they all show when Dark wizards or enemies are around, but you don't want to rely on them too much, they can be fooled…'

He gazed for a moment into the cracked Foe-Glass; then turned his back on it.

'Well, I've been thinking about the sort of stuff we ought to do first and - er -' He noticed a raised hand. 'What, Hermione?' '

I think we ought to elect a leader,' said Hermione. '

Harry's leader,' said Cho at once, looking at Hermione as though she were mad, which I agreed with. The whole point of this was for Harry to lead us!

'Yes, but I think we ought to vote on it properly,' said Hermione, unperturbed. 'It makes it formal and it gives him authority. So -everyone who thinks Harry ought to be our leader?'

Everybody put up their hand, even Zacharias Smith, though he did it very half-heartedly. 'Er - right, thanks,' said Harry, who could feel his face burning. 'And - what, Hermione?'

'I also think we ought to have a name,' she said brightly, her hand still in the air. 'It would promote a feeling of team spirit and unity, don't you think?'

'Can we be the Anti-Umbridge League?' said Angelina hopefully.

'Or the Ministry of Magic are Morons Group?' suggested Fred.

"The Fudge is Sludge Committee?" said Amy, which drew some laughter.

'I was thinking,' said Hermione, 'more of a name that didn't tell everyone what we were up to, so we can refer to it safely outside meetings.'

"The Defence Association?' said Cho. The DA for short, so nobody knows what we're talking about?'

This was a good idea, but I had an even better one.

'Yeah, the DA's good,' I said 'Only let's make it stand for Dumbledore's Army, because that's the Ministry's worst fear, isn't it?'

There was a good deal of appreciative murmuring and laughter at this.

'All in favour of the DA?' said Hermione bossily, kneeling up on her cushion to count. That's a majority - motion passed!' She pinned the piece of parchment with all of our signatures on it on to the wall and wrote Dumbledore's Army across the top in large letters.