"Are spells actual things? Are we making things when we cast spells?" I was trying to pin down some questions I was having – there had to be some element of normal physics that wasn't completely shattered by the sheer impossibility of all of this.
"It is a thing made of magic, I suppose you could say. Or it's just magic itself and no thing at all – what's the difference, exactly? You can see some spells, young man, even if the simple levitation is too weak to be seen."
"Okay, wow, you can see them, so they must be pretty slow. So is there a distance limit? Could you fire a spell miles away? Do you need to shoot it at an angle?"
"An angle? Ah, no, no, it isn't quite like that, spells go in straight lines, it isn't as though you threw a rock. You might imagine all spells have perfectly balanced levity." He nodded and started gathering his papers, obviously feeling the questions were wrapping up, or at least his patience for them.
"Sir, I can honestly say that's really quite surprising. The arc a rock takes really doesn't seem to be caused by it's weight. Anything would take that path, even things with no weight at all, if they went that slowly. It's space itself that's curving, or at least, that's what it seemed like, before I came here, before I saw all this..."
"Ah, yes, without magic it's easy to get things quite wrong. That's why we recommend schooling start at the quite young age of 11. Don't want students getting the wrong ideas, you see." He nodded, thinking himself very well versed on correcting the misconceptions of newer students, particularly those raised in non-magical families.
"But what about black holes?"
"If things go in straight lines, even in the presence of gravity, what about the things so massive that time itself cannot escape? Heck, if spells can come out of black holes, maybe people could too, it isn't like you'd have to be constrained by the classic rocket equation..."
"Ah, yes, that was a big problem until Merlin's Black Castle Evaporation Ward. The terrible fortresses that would destroy those near them but keep a wizard inside essentially unharmed... quite a puzzle, but rest assured, nothing you need to worry about, I believe the ward covers all of Magical Britain, at least, and probably some area beyond that. That wasn't nearly as disruptive as you might think, compared to the warding against High-Pressure Strange Gloop Evaporation Resistance. A simple modification of a basic cooking charm, to make sure boiling water didn't evaporate away, and they say Atlantis was lost to it, or at least hopelessly scrambled. We're more careful about the materials we make in experiments these days, of course."
I was going to need to sit down. How many bizarre protections did the world need for Magic to be safe? Was this why we needed to remain a secret – that even just ignorant wizards smooshing things together caused two different apocalyptic-level dangers? Surely density alone isn't even the most dangerous thing about magic powerful enough to create discontinuities in space itself, if that old train platform was any indication. I'd need to make sure not to be too detailed in my letters home. My parents cannot, under any circumstances, ask any questions a wizard might have interest in answering.