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Potential and Tension

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“Any questions?” McGonagall queried. The students fidgeted, waiting to be dismissed. Hermione finally raised her hand. She had been oddly subdued during the class. “Miss Granger?”

“Professor, I’ve been thinking... We will eventually learn to transfigure or conjure practically anything inanimate. Is that correct?”

McGonagall nodded. “That is correct. There are some interactions when conjured or transfigured life interacts with untransfigured life—such as when conjuring food—and there are certain difficulties around precious metals, but generally, there are few limitations.”

“But what stops anyone from conjuring poison gas, or a nuclear bomb?”

“This is a longer question, Miss Granger. I would be happy to answer it after class.” She looked around the room. “Any other questions?”

There were none, and the class was dismissed. Ron also turned to go, but saw that Harry, Dean, Justin, and a few others had stayed behind to await McGonagall's explanation. He leaned over to Harry. “What's a nucular bomb?”

“I'll explain later,” Harry whispered back, and McGonagall began.

“Back when you learned to transfigure a matchstick into a needle, have you considered what metal the needle had been made of? Silver? Steel? Aluminium? Nickel?”

Nobody had.

“Now, what material would it have been?”

Several hands went up, including Hermione's. McGonagall called on Justin.

“It would be steel, right? Because that's what needles are usually made of?”

“Two points to Hufflepuff. Yes, though it would be more accurate to say that in your experience of needles, that is what they would have been made of. Now, if you had wanted to make it out of aluminium instead, could you have?”

There was more hesitation this time. Hermione had raised hers tentatively.

“We would have had to handle aluminium needles? Though, what if we handled steel needles but aluminium cans and focused on that?”

“Two points to Gryffindor. You could force the needle to become more aluminium than steel, but you would need to know aluminium very well—perhaps far beyond merely handling aluminium cans. At the very least, you would need to be able to tell the difference between steel and aluminium with your bare senses, perhaps with more than one. The concept of aluminium must be as natural to you as the concept of a needle. Otherwise, how would your magic know which metal you wanted?”

“So in order to transfigure poison, you have to have been poisoned by it?”

McGonagall nodded.

“And in order to transfigure something into uranium, you would need to know uranium well enough to distinguish it from hundreds of other metals and alloys?”

“That is correct. After the Muggles began to test their nuclear bombs, the Unspeakables researched the question of whether a wizard could conjure one. Fortunately, we discovered that even if one managed to obtain a small amount of fissionable uranium or plutonium to use as a reference, they would hardly be able to distinguish it from its more inert isotopes or even just tungsten. Using the Doubling Charm had similar problems. The bigger concern was that a wizard might steal one from the Muggles.”

There were follow-up questions, about isotopes and fission, which McGonagall fielded as best as she could, and Hermione helped as well.

“McGonagall knows a lot about Muggle science,” Harry remarked as they hurried back to the Great Hall for lunch.

Hermione nodded, still lost in thought. “Experience something to conjure it… I wonder…” she mumbled and trailed off.

The year continued. There were classes and Quiddich and petrifications, and a mad scheme to brew a potion in secret. Hermione proved to be a harsh taskmistress, insisting that they finish the potion by the end of the term, yet oddly conflicted about it. In the end, on the morning of 21 December, she handed them the flasks of Polyjuice and the candies laced with Sleeping Draught, apologetically wished them the best of luck, and boarded the Hogwarts Express to London.

Her plan went off without a hitch, but no new information was gained, except that Malfoy didn’t know anything other than ancient history.

Hermione returned on the third of January, looking like she had spent the whole break running from a mountain troll, and visibly favouring her left arm. To their questions, she gave a pained smile and promised to tell them later, before heading off to the hospital wing.

Harry and Ron insisted on keeping her company; they caught a glimpse of blistered burns covering much of Hermione’s left forearm, before Pomfrey shooed them out. The Hermione that walked out half an hour later was far more subdued. “An… accident. The Muggles did the best they could.”

The classes resumed. Harry found the mysterious diary and spoke with Tom Riddle, learning about Hagrid’s expulsion and about the acromantulas.

Before he knew it, it was early May, and the morning of the match against Hufflepuff, and another whisper in the walls. Hermione clapped her hand to her forehead, and ran off to the library.

* * *

Harry was just mounting his broom when he heard loud clanking and the thunder of hundreds of heavy footfalls coming from the direction of the castle. Indeed, a veritable army of suits of armour and stone statues marching toward them, McGonagal in the lead. The Grey Lady and the Fat Friar floated overhead. McGonagall stopped, and her animated army split into two groups, quickly surrounding the stands. She raised the huge megaphone she had been carrying to her lips.

“The match is cancelled!”

Students booed, and even Harry tried to object. McGonagall’s next words brooked no objections.

“Everybody is to evacuate directly to Hogsmeade on foot. There are no exceptions! Under no circumstances may you return to the castle! You will be escorted by the statues. You are not to leave their cordon until you arrive at Hogsmeade! At all times, look only down at the ground in front of you! You will be given further information at Hogsmeade. I repeat, proceed in an orderly fashion, keep your eyes on the ground, stay between the statues. All will be explained once we have arrived.”

* * *

Hermione looked up from the book. So it was a basilisk after all.

The library was disturbingly empty. Of course—the Quiddich match was just about to start. And, Slytherin’s monster was out on the prowl, perhaps going after her even as she sat there. For once, Madame Pince was nowhere to be seen.

Never before had she missed Muggle telephones so much. Perhaps the wizards had a replacement? She needed to find a professor.

There was one bit of good news. Each petrified victim was a ticking time bomb—an eyewitness who could identify the monster and perhaps the Heir of Slytherin themselves as soon as revived—yet all were intact in the hospital wing, awaiting their mandrakes. Therefore, the Heir either could not or would not finish off the petrified victims. This suggested that this form of petrification conferred some form of invulnerability.

She needed a portable mirror. She tried transfiguring one of her notebooks to have a reflective surface. It was barely usable, particularly in the dimly lit hallways of Hogwarts. It would have to do.

Ripping a page out of the book on creatures was sacrilege, but she needed every backup plan she could get.

She ran into Penelope Clearwater at the library entrance. The sixth-year Ravenclaw proved far more adept at transfiguring a mirror.

And then, she felt it.

Her winter holiday experiments had produced two side effects. One was a branching web of scarring over her left forearm, that not even Madame Pomfrey’s ministrations had been able to heal; this meant long sleeves for the foreseeable future. The other she only discovered at King’s Cross, when she walked past one of the high-voltage transformers that drove the electric locomotives. She could feel the current flowing through its coils; and it felt like staring into the Sun while hearing a police siren at point blank range. Once at the electronics-free Hogwarts, she tried to get a sense for how sensitive to electric fields she had become, but without a reliable source of alternating current, her experimentation had been limited. She could vaguely sense human bioelectricity, though even as close as a metre away it was indistinguishable from background noise.

But this was no human bioelectricity. The creature was—or at least its nervous system and musculature were—enormous. All too soon, the approaching blur resolved itself into the shape of its eyes and brain and jaw muscles, just out of her and Penelope’s line of sight, not ten metres away.

Penelope was raising the mirror to peek around the corner. In a moment, she would be petrified. All Hermione had to do was look in the mirror as well, and join her in petrification, with the hope that someone would find the note in her hand and put the clues together.

But, she didn’t have to do it, a rebellious, Gryffindor part of her mind reminded her. Unlike Penelope, she could see the basilisk with her eyes closed. She could evade it. Maybe even give it a shock it wouldn’t soon forget. It’s what Harry would do in her place, certainly. Of course, even being immune to its gaze would not save her from being crushed, poisoned, or just bitten in half by the creature—whose brain she could now sense all too clearly but whose tail was still a blur.

But, who knew how long it would be before someone found the note and put the pieces together? What if Madame Pomfrey just threw it away? Decision made, Hermione shut her eyes, took a step back, clenched her fists, and concentrated. The feeling of her hair brushing past her ears to stand on end was all too familiar.

Penelope’s bioelectricity stopped abruptly. There was no thump of a falling body, so at least she was petrified in place and not dead. She heard the mirror shatter on the floor. That had been her last chance of a safe petrification.

Hermione continued to walk backwards, gathering more charge, feeling the tension rise. Small charges began to slip her control and arc into the air and between her and the walls and floor. She had found, in her experiments, that she could reach higher voltage when angry, and so she turned her thoughts away from this creature, and to the Heir of Slytherin. The basilisk was just an animal. But the Heir—they were trying to terrorise her out of Hogwarts, cheered on by the likes of Malfoy. How dare they?! The basilisk turned the corner, aiming its gaze at her.

Hermione raised her arms and unclenched her fists. Her fingers straight and splayed, pointing towards where she could sense the monster’s eyes, she pushed.

She could hear the loud crackle of the electric arc, bright enough that she could feel it through her eyelids. The creature hissed in pain and reared. She continued to push.

She let up only when she felt the arc strike the ground, the voltage having fallen too low to reach the monster. The air smelled of her burned sleeves, ozone, and what she hoped was burned basilisk flesh and not her own.

The basilisk did not seem ready to give up, so Hermione continued walking backwards, as she built up another charge. She could sense its jaw muscles shift as it opened its maw, which she knew—from reading, since her eyes were still shut—was full of envenomed teeth.

She pushed again, this time aiming at its mouth. She heard its jaw clench shut.

Harry or Ron would have probably said some pithy line about shutting up, but Hermione just turned and ran, squinting at the ground to keep from tripping.

After the third time her shoulder scraped a hallway wall, she chanced looking up. The basilisk’s nervous system was no longer in her range and hadn’t been for a while. Predators usually did not pursue prey that had hurt them, so that made sense, in retrospect.

She continued in a steady jog, keeping her gaze low.

“Miss Granger! What happened to you?!” It was McGonagall.

Hermione forced herself to get to the point. “Professor! There’s a basilisk in the castle!”

“What?! Whatever do you…”

“The Slytherin’s monster—it’s a basilisk.”

“Miss Granger, that is preposterous. A basilisk’s gaze kills; it does not petrify.”

“But it’s the only thing it makes sense! Harry could hear it—and he’s a Parselmouth. And everyone who’s been petrified only saw its gaze indirectly—like through a mirror. And the roosters… Please, believe me! If I’m lying, expel me later!”

McGonagall looked her up and down, then came to a decision.

“If what you are saying is true, then we must evacuate Hogwarts immediately. We shall discuss what happened to you later. The hospital wing is not far. Can you make it there on your own?”

Hermione shook off a wave of lethargy. “Yes. Yes, I can.”

With a wave of her wand, McGonagall conjured a mirror and handed it to her. “Go straight there.”

Hermione nodded, noticing that her hands were shaking as she took it. Then, she remembered. “Professor, it petrified Penelope Clearwater, near the library. And it’s using the pipes to get around.”

McGonagall nodded. “We’ll take care of her. Go.”

Hermione went. She jumped when she saw a silver cat (whose bioelectricity she could not sense) streak past her, only to disappear through a wall. She jumped again when the suits of armour next to her came to life and marched off. In the end, she arrived at the hospital wing, only to find the doors locked, with the Bloody Baron standing guard.

“You are expected.” He phased through the door, at which point it was unlocked and Madame Pomfrey pulled her inside.

“Are you hurt?”

“I don’t think so…”

Pomfrey waved her wand, muttering diagnostic charms. “It looks like you are merely tired and in a bit of a shock. You can lie down over there.”

But Hermione’s rest was not to be, because in a burst of flame appeared Dumbledore, his phoenix riding on his shoulder.

“Thank you, Fawkes. Please continue to patrol.” The phoenix disappeared with a caw, and the wizard turned to Hermione. “Miss Granger, if your inference proves correct, you have done a great service to the school, not to mention help right a terrible wrong of fifty years ago. But, I am afraid that I must impose on you further. Can you explain why you believe that Slytherin’s monster is a basilisk?”

Hermione took a gulp of a potion Pomfrey had just handed to her—no, just strong coffee with a lot of sugar—and repeated the explanation she had given to McGonagall, albeit more cogently. Dumbledore nodded.

“Fascinating. That a basilisk’s gaze can petrify if viewed indirectly or through a ghost is a novel discovery, one which may save lives in the future. I will make sure that you receive full credit for it. Now, before I relocate you to Hogsmeade, there is one item I would like to confirm.”


“Miss Granger, did you fight the basilisk using lightning?”

“I…” Hermione stuttered, turning pale. He knew! She had hoped to elide that, or bluff her way through an explanation, maybe give Penelope credit for distracting the basilisk while she ran, but this was far too specific. Silly girl, thinking that she could fool Albus Dumbledore himself! And now, expulsion was the least of her worries. “I… I didn’t know it was Dark magic, I swear!”

Dumbledore frowned. “Miss Granger, if could please explain yourself; how did you come to practice Dark magic?”

And so she explained. She told him how she tried to look up electricity or lightning spells on a lark, and found that there weren’t any. She told him about her unrelated worries about the potential for Transfiguration to be used for poisons or even nuclear weapons; how McGonagall’s reassurance stuck with her, and how she connected lack of lighting spells with lack of personal experience of electricity. How she connected it to some reading on Accidental Magic. And, how the worries about the Heir of Slytherin pushed her to give it a try.

How she had started with a battery on her tongue, but soon concluded that a stronger stimulus was be needed. The 240 volt mains power did elicit an encouraging reaction, so she persevered, careful to send the current only through her left forearm in order to protect her heart and her wand hand. How she eventually succeeded in directing electrical currents and potential—at the cost of second-degree electrical burns. And how she had, later, discovered a degree of sensitivity to electric fields.

And then, how even with Madame Pomfrey’s burn salve, the burn scars on her arm had remained, and how she had realised then that it had to be Dark magic; that she had resolved not to tell anyone, but continued to practice, just in case the Heir of Slytherin came after her—since the damage to her soul had already been done.

And, finally, her overhearing Harry in the morning, confirming her suspicion in the library, and her confrontation with the basilisk. Dumbledore asked to examine her scars, then rendered his verdict.

“Miss Granger… First of all, let me reassure you that you are not in trouble. Your inference was not invalid. You may have inadvertently performed Dark magic of sorts, willingly inflicting pain and scoring flesh—and on your left hand, too—to obtain power. That is why the scarring could not be healed with magic.

“This type of magic will not be taught at Hogwarts as long as I am its headmaster, and I would strongly advise you against trying to obtain additional powers by exposing yourself to other hazards—not least because they may not be as controllable and predictable as Muggle electricity.

“However, while the magic you had performed over your winter holidays was, in a sense, Dark, it was mitigated by the sacrifice being all your own and done in ignorance rather than malice. In my opinion, you have not tainted your soul. And, I would not consider the use of your acquired abilities to be Dark. You have done nothing deserving of punishment, and, if you like, I will keep your secret. It is up to you, of course, but keep in mind that you can only reveal a secret once.”

Hermione slumped, visibly relaxing. “So then, I may continue to practise, but I shouldn’t teach it to Harry and Ron?”

Dumbledore nodded. “Indeed. In fact, given the nature of these kinds of magic, I would not guarantee that were Mister Potter, Mister Weasley, or even a person of equal talent to yours replicate your procedure using your instructions, they would get the same result. It may well be that the magic requires one to discover the procedure on one’s own, to have grown up around Muggle electricity, or some other element that we are in no position to discover.

“Now, secondly, it seems that you have compounded your merit of discovering the monster’s identity by risking your life to wound the monster and warn others. The school is again in your debt.

“Thirdly, it may well be the case that your invention can be developed into a wanded form that can be taught.”


“You may have read that a small electrical discharge is not an uncommon expression of Accidental Magic in response to the young wizard or witch being grabbed. A wanded form of it exists as well, to briefly electrify one’s skin for a short discharge, akin to static electricity. You will not find it in standard spell books, however, but rather taught to pureblooded ladies to politely but firmly repel suitors who take liberties.

“On the other end of the spectrum, there is, in fact, a spell for a bolt of lightning—a very obscure and difficult one. I know of only one wizard to have truly mastered it: Gellert Grindelwald. Voldemort did attempt it in some of our confrontations, but to limited effect.”

“And you, Professor?”

The old wizard smiled. “My talents lie with fire, as Fawkes can testify.

“However, that spell’s conception of electricity came from lightning: a force of nature, a wild beast that only the most arrogant would presume to even try to predict and only the mightiest could have a chance of taming: very powerful, yet also nearly impossible to cast. Conversely, the shock spell’s conception comes from a discharge of static electricity: surprising, painful, but ultimately harmless and inconsequential.”

Hermione considered. “But Muggle electricity is powerful but already tame?”

Dumbledore nodded. “Better yet, it is a regimented creation of human will, born to serve. It may therefore serve a basis of a spell suitable for a Defence class, and with your hard-earned innate understanding of it and some effort, you may well be able to find a reliable wand motion and incantation for it. But, let us leave that for the future.

“Evacuating Hogwarts has bought us time to assemble aurors and roosters, but there is much work to be done—not least identifying the Heir of Slytherin and locating the Chamber of Secrets. Do you have any questions before I relocate you to Hogsmeade? In particular, would you like me to mend your robes?”

“Yes, please. But Professor,” Hermione hesitated, “How did you know?”

“Elementary,” he smiled, “When Minerva’s messenger reached me, I first sent Fawkes—who is immune to a basilisk’s gaze—to confirm that the basilisk was gone, then came myself to retrieve Miss Clearwater. On arriving, I smelled ozone. On further inspection, I found droplets of what my spell told me was basilisk blood. On seeing your burned sleeves, I had a hypothesis, which I then proceeded to test.”

“Basilisk blood?”

“Based on what you have told me, I believe that it may have bitten its tongue. It is unlikely to succumb to its own venom, but its health may suffer temporarily. Similarly, only time will tell whether you had inflicted permanent damage to its eyes or temporarily blinded it.

“Now, off to Hogsmeade with you. Tell Madame Rosmerta and Ambrosius that your butterbeer and confections are on me.”