"This is as good a place as any," she said in a quiet tone, almost a whisper. "At least we have water."
He had no idea how long they stayed there, because he couldn't easily tell time down in the cave. He Conjured wood for a fire and a roasted goose off some hapless inn's serving table, and then both of them immediately went to sleep. They were both very tired, and though he'd been a bit worried about not posting a guard, he realized that there really wasn't anything down there that could hurt them. He did raise a Ward that kept out everything but air before he went to sleep. He was confident that there was nothing down here, but he wasn't going to take any chances.
He had no idea how long they slept, but when both of them were awake, they ate breakfast without conversation and then set out again. The going was easier and easier as the passage continued to enlarge and become easier to travel as it descended, almost like a grand gallery with a ceiling higher than they could see and a flat floor that almost seemed like a road. It rose and fell, but he could tell that it still predominately went down.
They travelled some time before a strange sound reached both of them. It was extremely faint, barely audible, but the nature of the tunnels carried the sound to them. After pausing to filter out the echoes in his mind, he realized that it was a faint hissing sound, like what he remembered the volcano on Sha'Kari sounded like in the cauldera. But it was a slightly different sound, and he could distinctly hear moving water as well. And bubbling, like a kettle of boiling water, or maybe an area of very gentle rapids in a small stream.
"Sounds like water," Jesmind whispered, peering into the gloom ahead. She could only see about a hundred spans ahead, just as he could, but the reflex to try was automatic.
"I think it is," he answered in the manner of the Cat, a means of communication that was completely silent, and would not interfere with his ability to hear. "Let's go see where it is."
"Let's be careful," she said. "I think I've caught whiffs of some kind of animal in the air. This air is too damn thick and laden with other smells for me to be too sure, though."
He nodded, bringing his staff out of the elsewhere. The passage was more than large enough for him to wield it.
They padded along carefully for a surprisingly long distance, as he realized that the tunnel was funnelling the sound to them from a great distance away. The air began to move, to blow very gently in their faces, and it carried the smell of water with it, along with the tang of minerals, and the air seemed both humid and strangely warm. Curious now, both of them picked up their pace just a little bit, confident that the air blowing in their faces would bring the scent of an enemy to them before the enemy knew they were there. The air kept getting warmer and warmer, until it was almost unpleasantly so, and it grew veritably sticky with humidity, so much so that Jesmind took off the fur-lined shirt he'd Conjured for her. The passage descended again, but now there was a very faint, ruddy light at its end.
Tarrin stopped, remembering the last time he'd seen a ruddy red light at the base of a descending passage. "What's the matter?" Jesmind asked in the manner of the Cat.
"That might be an underground volcano," he told her. "Something has to be making that light. It might be lava."
"Well, let's keep going," she said. "If it gets too hot for me, I'll stop, alright?"
"Alright," he nodded, and they started down again, more cautiously this time.
They padded down to the end of the descent, as the air got hot, but not dangerously so. Tarrin did smell some sulfur and other minerals that he remembered smelling in the volcano, but it wasn't nearly strong enough to be dangerous. They reached a bend in the passage and peeked around it, and Jesmind laughed audibly when they saw what was on the other side.
It was an absolutely massive opening, a great chamber of empty space at the very heart of the mountain itself. The light wasn't from lava, it was from some kind of strange luminescent fungus or growth that was literally covering all the ceiling and walls, but not the floor. It was a huge circular chamber with an arching domed roof, the top of it more than two hundred longspans from the floor, cast in the strange red light of the luminescent material covering its walls and ceiling. The floor of the chamber was surprisingly flat, but there were multiple rimmed pits in it that were filled with water or dark, thick mud, and both water and mud laid in thin pools in depressions on the wide floor, all of which had tendrils of thin steam rising up from them. The air was hot, sticky, and he realized that the mineral smells were coming from the water itself. The hissing and moving sounds they'd heard were coming from the water, from the hissing of the water and mud that boiled to the sounds of the bubbling water churning in its stone pools, like large kettles on a stove.
It was a hot spring! A hot spring in the middle of the mountain's heart!
"Incredible!" Jesmind said in wonder, looking around. "It's a hot spring!"
"Let's be careful," he said. "Sometimes hot springs erupt into geysers. It won't hurt me, but I think you may not like having boiling water sprayed all over you."
They waited where they were for a while, then carefully circumnavigated the chamber around the walls, wary of any trembling in the floor or rushing sound that would herald an eruption. But none happened. They reached the far side of the chamber, where a wide tunnel led up, and somehow Tarrin sensed that this hot spring was at the bottom of the cave system, that it would be up now instead of down.
"I kind of like it here," Jesmind said. "I've never seen a place so exotic."
"It may be dangerous."
"Well, do your magic thing and find out if it is or not," she said. "I'm tired and I'd like to rest a while, and this place looks pretty good."
Glancing at her irritably, Tarrin knelt and put a paw on the floor, then sent flows of Earth down into the stone. He didn't like using magic as they got close to Val, but what he was doing was very gentle, very passive, and required very little energy. He sent his weave deep into the ground, seeking out the source of the hot spring, and once he found it, he inspected what he found there. The stream that they'd seen before dropped down close to a pocket of magma, which heated it and caused it to rise up here. It was very steady and consistent, and he sensed no erratic motion of water or steam that would cause a geyser. The springs here were very stable.
He told her so, which made her almost squeal in delight. "Let's find one that won't boil the meat off me!" she announced, rushing back into the chamber like a little girl with a new doll.
"What?"
"I want to take a bath!" she called after him.
Take a bath? Then he realized what she meant. A hot bath always was relaxing but a bath where the water would never cool off was a rather attractive concept.
Tarrin looked around. The place was a bit warm and a little muggy, but it had its own light, plenty of water, and it was in the absolute center of the mountain. He couldn't get any safer than this. This would be a perfect place to stop so he could figure out how to keep the Demons off of them… and he had to admit, the idea of bathing in one of those hot springs was rather attractive.