Elves, dwarves, and humans once walked this land and built on it. For the past eight hundred years, no sapient being has disturbed the ruins.
"Yeah, that too."
Eventually Tem finishes his sketch and they move on from the throne room. The rest of the palace yields only a handful of desk-drawer knobs and damaged pens.
The next building they check used to be a bakery. Tem identifies the metal plaques scattered about as reading "Breads", "Cakes", "Cookies", and "Delight of the Week". There's also a metal box with a dial on it.
Hot box! It's an oven. Also it feels like the dial will come off in her hand if she's not careful.
She's careful. She summons the others to check it out.
Tem can read the numbers on the dial; presumably they're temperatures. And yup, turning it changes the amount of heat they can feel emanating from the box.
"This is another one we can't bring back with us. Now that we have several artifacts we can bring back, it might be worth trying to take this one apart."
"Is it going to be - made of interesting stuff, not just a box?"
"I don't know! We have no idea how artifacts were made; if we take it apart we might find some clue to its construction and from there to how it was enchanted."
"Cool. Do you need help?"
He pulls the dial out, sets it down on one of the larger, flatter pieces of rubble, and examines the resulting gap between the top and front panels of the oven. "I don't expect to, but you're welcome to lend a hand."
Derron and Chaenath watch excitedly as Tem pries the top panel up. It isn't just a box! There are channels cut into the metal, lined with blue and red paint.
"Ooooh. Do those patterns mean anything to you?"
"Not unless you count a mystery worth solving!"
Copious amounts of poking, prodding, notetaking, and mana-flow-observing ensue. Eventually they determine that the channels guide mana and give it some sort of extra property that mana in people and animals doesn't have. By the time they're done, it's high time everyone got some sleep.
Cayra doesn't need to sleep but she might as well.
The expedition all sleep on the boat; they can rig up a spare hammock for Cayra if she likes. In the morning they debate the merits of heading back to Pinehedge with what they've got, versus trying to push their supplies go to Tisfaat and back.
"I've already been there for you," she points out.
"Yes, it would just be a question of bringing back some of the other objects you mentioned and four pairs of eyes catching things one pair might have missed. I'm not sure it's worth it; we'd have to follow the river for water instead of going as the crow--or the Cayra--flies."
"And we've already learned things the folks back home will find very exciting," says Tem, waving his notes on the colored mana channels in the oven. "Let's get this stuff to the Archives so they can start working on it, then go explore the rest of the continent."
"It's all the same to me, where you guys usually live is new for me."
Eventually they decide that the wonders of Tisfaat can wait for a second run. It helps that they know where it is, and can put the boat at the closest workable point on the coast and head overland instead of following the river. They set off back for Pinehedge with their wealth of notes.