She goes back to pumping while she talks. "Runes, though it's as much a language as a standard runic system. Most runic magics are a couple dozen symbols, you know - this one's a thousand for fluency, thousands more for mastery."

"There's more than just the large runes; they're surrounded by smaller runes, barely visible - most write the auxiliary runes so they'll vanish, to preserve trade secrets. These define everything the pitcher's supposed to do, down to the temperature of each rune and that they should turn off when dry, to preserve energy. It's easiest to get the major runes themselves to do stuff, though you can impact what they're inscribed on, too. The system's so far unique to this island; most of us are descended from the same world, and it was native there."

"Can anyone do it, or do you have to, like, in be blood-related to someone from your world or live here or something?"

"It's fairly rare to pick up, but I think anyone? Nearly everyone I know who uses it is descended from my world, but that's probably just because we're prideful enough not to go with an easier system. Though this one's more flexible and - exact - than most, I think. Makes a fine niche for artifact creation."

"It looks amazing and is so pretty and I wanna learn it."

"...You can find an apprenticeship? Or I can sell you a copy of my notes from mine. And a dictionary, I can pick up a new one later. There's not really... Well, grammar books or formal classes, it's all apprenticeships and such. I can give you a discount on the notes, too, if you give feedback on them next time you're in town - I'm planning on publishing usable how-to books once I'm established."

"Ooh yes I'd love to have notes!"

She hands Tetsuma the full buckets (easier to balance with both) and starts leading the way inside. "They're not optimized for learning from scratch - I mostly sell them to apprentices - but I've also got some old drafts where I tried articulating basic grammar for a general audience, sort of starting on the book, that I'll throw in. How does ten Suns sound for a price for the notes?" (It's about half the normal cost of a book, in the local currency.) "And I'm not off work until after dinner, but I can give you a grammar lecture while working."

"Ten Suns sounds like a very fair price, and I'd love to learn whatever you have to teach me."

So they can chat, then, until Feid gets called away to help with dinner preparations. (She gets some light teasing from her coworkers over conscripting Dayo and Tetsuma into helping with the buckets. They need a lot of water, for drinks, cooking, washing, and such. She also turns down Tetsuma's offer to help with jutsu - too unknown.)

The runic system is basically a magical programming language. Each 'word' gets its own symbol, which is why there's so many. Effects need sentences formed of rune clusters defining parameters, which has such and such basic grammar rules. It's mostly useful for altering the nature of materials - Tetsuma's first thought is 'better weapons,' which Feid confirms that yes you can do, though almost no one bothers what with the ley making war a logistical headache. More common's stuff like temperature changes, or durable cloth and tools. Advanced practitioners can do complicated stuff, like a barrel that will keep its contents perfectly dry. 

Can it do more obviously magical effects like making stuff float, emit light...?

...Float, not easily. Gravity's very insistent, and you'd have to be careful with your parameters to not break whatever, or make it unsteady. Light, sure. Getting a rune to glow is about the most basic exercise, getting the object itself to glow is harder.

She pays rapt attention and asks lots more questions.

And Feid answers them, though she does have to go work in the kitchens after a while. At that point they still have a bit before dinner's served.

She'll chatter excitedly at Tetsuma about More Magic!!!!!

Tetsuma thinks her girlfriend is the most adorable, but is also excited about shareable magic.

"Looks a lot less complicated than kanji, too - fewer symbols, and they're nice and straightforward."

"That's because kanji is absurd, love."

"It's not that bad, especially if you're just going for basic fluency. There's patterns to them... I wonder if the runes have similar patterns? That'd be nice and convenient."

Well do they?

If they ask Feid after dinner: well, some. Less advanced runes are visually simpler, and more advanced runes sometimes contain smaller versions of related runes. Like, the 'darkness' rune (which is really complicated to use) is tripartite, and one of those parts is the 'light' rune.

And light's simpler? Why?

...Because darkness isn't actually a discrete thing and light is? And unlike some magics this particular runic system doesn't have Dark as an atomic concept. Also light and heat are both common waste products, you can produce them by accident, getting the runes to make them on purpose is easy. Making light go away though is fairly hard, you have to get the rune to absorb not just light hitting it but nearby light.

Oooh a sensible magic system, this is cool.

Yeah that's probably related to the increased precision thing, it's probably easier to have specific effects when you're not flagrantly violating physics. Though most usable magic systems have some kind of internal logic, at least enough to be studied.

So: head over to her apartment?

Sure!

It's pretty close to the inn - about a short block away and then up a few levels - and small. All of the walls are covered in either bookshelves or diagrams, and most of the surfaces are cluttered with writing supplies and various miscellaneous items. 

She pulls out a drawer in a narrow cabinet, which turns out to be full of paper, and produces a thick packet of loose papers tied together with a string. "Here's a copy of the notes, and - " some rummaging - "A draft on grammar. D'you want a dictionary, too? The bookstore sells them, but they don't open until the second quarter of the day." (About four hours after dawn - past when Sarati had wanted to leave.)