Apparently the technician drilling holes knew more about drilling holes than she did about telling time, because they didn't catch up to McKay and his group in the lava tube. When they came out into the drizzly rain that was still coming down, they found him in the Jumper, supervising the offloading of several crates of far more delicate equipment – diagnostic stuff for the most part, extra components, things like that.

But there was also a metallurgical tester that Rodney himself had brought, because he wanted to see why the walls of the lava flow were impervious to the sensors of the Jumpers – and hopefully anything the Wraith might have as well. Melony would be doing tests on it also – presuming she managed to get hold of a Wraith dart – and if it turned out that even the Wraith technology couldn't scan through the stuff, then it was definitely worth figuring out why.

They went up the ramp just as the final crate on anti-grav sleds were being offloaded, and almost ran into McKay, who about jumped out of his skin.

"I thought you two were checking out the lava tubes?"

Mitchell nodded, "We were."

"What do you know about underground rivers?" Sheppard asked.

"I know they're water… running underground."

Melony smiled at the annoyed look on Sheppard's face, but really, he should have expected an answer like that – she had.

"Cute."

Rodney couldn't help but look smug – he loved every chance he got to annoy Sheppard and the other military people, which included Mitchell – although he didn't do that very often out of pure self preservation.

"Did you find an underground river?" He asked.

Mitchell nodded.

"Yes."

"Did you test the water? Is it hot?"

"No, it was cold."

"It's probably rainwater runoff, then. Maybe even fed by that little crack in the main chamber. Was it moving fast?"

Mitchell shrugged.

"We didn't really test it, because we didn't have any safety ropes or anything, but it wasn't a raging torrent or anything."

"Then we probably couldn't use it to power the electrical systems – not only are we not sure if it's a continuous source of energy, but it's not as efficient as the thermal energy is."

"It's quite a ways down the tunnel, too," Melony added. "We'd be stringing wires for the next couple of weeks."

He looked at her.

"Of course, if it's good water, you can always use it for drinking water – or showers or bathing. It's not like you don't have a large supply of warmth to heat the water with."

She wasn't so sure she wanted to run pipes any more than she wanted to run wires, but she supposed it was something worth looking into – further down the line, maybe.

"True."

"Are you going back to it?"

"As soon as we get some proper equipment, and maybe a bite to eat. Want to come?"

"How far down the tunnel is it?"

She shrugged.

"A mile or so…?" She looked at Sheppard, who nodded his agreement.

"Probably more."

McKay made a face that told them what his answer would be long before he actually spoke.

"I think I'll pass. I should probably stay close – in case someone needs me."

He was probably right, she knew.

Sheppard knew it, too, but he couldn't help but smile. McKay was never one to volunteer for extra exercise if he could avoid it.

"We might need you there," John told him. "You know… to test the water or something."

Rodney scowled, "Just make sure you wait half an hour before going in if you're going to have something to eat first."

Melony snickered, and slapped the Major on the shoulder.

"We'd better get going."

He nodded, and Mitchell turned to McKay.

"You need anything before I go?"

Rodney shook his head; he and Melony had discussed everything thoroughly, and he knew what she wanted and needed and he could do most of it without her help. Besides, he liked supervising things like this.

"Bring me back a surprise."

"We'll bring you back a lava lizard skin," Sheppard told him.

"You do that."

They stopped just long enough to grab up a couple of fifty foot ropes and some strap harnesses, and then left the Jumper and headed back for the lava tube, passing the scientists with their crates, and loaded down with their own equipment.

OOOOOOOO

When they made it back to the main cavern, Carson was waiting for them, standing against the entrance of the tube they emerged from, and holding a couple of sandwiches wrapped in plastic that they'd brought from Atlantis.

"You found a river?"

Melony nodded and took one of the sandwiches from him, while Sheppard took the other.

"It's nothing too big," she told him, walking over to an unoccupied corner and sliding down to sit on an empty crate that had been turned upside down for just that purpose. "About fifteen or twenty feet across."

John came over and sat down beside her, glad for a chance to sit down for a little while – even though he wasn't as loathe to exercise as McKay was, he'd been on his feet most of the day.

"And you're going to go try and cross it?"

Beckett sounded worried, but Melony couldn't understand why. This time they were taking ropes and harnesses. It wasn't dangerous.

"We want to see what's on the other side," she told him, nodding. "Where the tube goes."

"And we want to see how deep the water is," Sheppard added, taking a huge bite of his sandwich.

"Can I come?"

Melony shook her head.

"Not with your ankle. It's a lot of walking, and it's uphill on the way back."

He frowned, but had to concede that she was probably right. His ankle was well on its way to being healed, but if he walked that far he'd probably do it more harm than good. He just wanted to spend a little time with her – even though she'd warned him that once they were here she wouldn't have lots of time for him.

As if she understood, Melony rested her hand lightly on his thigh and smiled.

"We'll bring you back a surprise," she told him.

He smiled, and sat with them while they ate, not trying to make conversation or anything, but enjoying Melony's company while he could, and listening to Sheppard as the Major told him all about the lava lizards that supposedly inhabited lava flows exactly like this one.