It was the third time Sam swung out at an offending branch and missed before Jack called her on it. Sam generally had good aim, but the knife she carried was sharp and Jack didn't fancy catching it between the eyes.

"Carter?"

"Yes sir." She sheathed the knife, completely aware of his reason for speaking.

"Hey, I hate this as much as the next guy, but I also like my skin right where it is."

"Sorry sir," she sighed in frustration. "It's just...I don't understand. I hate not understanding."

"Welcome to my world." That got a bit of a smile out of her.

"It should have stopped. Janet had no more exposure."

"What about those Nintendoes?"

"Sir?"

"I believe that O'Neill is referring to the phenomena known as neutrinos, Major Carter," Teal'c said from behind them.

Sam thought for a few minutes. Jack could hear the wheels spinning.

"Neutrinos would penetrate the caves," she pointed out, half to herself. Then her eyes widened and she reached for the naquadah detector. "Oh wow."

"Carter?"

"The naquadah, sir, it's all over the place."

"Would naquadah prevent the passage of neutrinos?" Teal'c asked.

"It's the only explanation I can think of. There's an awful lot of it. But that still doesn't explain how the infection worsens in the caves here, let alone how Janet got worse on Earth."

"You ever bake cookies, Major?" he knew she had, but he forgot what memories were associated with that, and when he remembered, he plowed on quickly. "Did you ever forget to add the baking powder?"

"No."

"Well I did. I still had cookies. They were still edible. They were just a little...unenthusiastic in the oven."

"So, you're saying Janet just needed the baking soda?" Jack could actually feel his eyes glaze over as Sam launched into full science mode. "Sir, that doesn't make any sense."

"Well no, but it was the best I could think of."

"Madness is the full extent of the disease without external aid," Teal'c summarized. "Inferno is only reached under catalyst. In this case, the sun."

"It's the spark, the last ingredient to set off rapid oxidation." Sam concluded.

"So we can prevent Fraiser from burning up, but we can't stop her from getting to sub-critical?" Jack asked.

"Yes sir."

"How does this help us?"

Sam stopped walking and turned to look back at him. There wasn't a whole lot of confidence in that look.

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"Daniel? Daniel!" The hoarse whispering was accompanied by an almost frantic shaking. "Daniel, please wake up."

Daniel groaned, then opened his eyes slowly. A full spectrum of emotion flashed through them, and he sat up as quickly as he could. He found himself strangely unable to support his head, and sagged back against the wall of the cave.

"How are you?" he managed to grate out.

"I feel surprisingly alive, actually," Janet replied. "Which is strange, because I had the most appalling..."

Janet trailed off as Daniel raised his freshly scarred wrist to adjust his glasses.

"Janet?"

"Oh God. I really did it."

"Janet, it's okay."

"No, Daniel it is not okay. I drank your blood."

"I prefer to think of it as my helping you stay alive."

"Daniel, stop. Stop trying to make me feel better. Stop hoping. Stop...just please stop." Her voice was becoming hysterical, high pitched. The madness was closing in again, bringing the blood lust with it.

"Janet, listen to me." Daniel took her face between his hands, ignoring the scars and focusing on her eyes. "I've dosed myself with a sedative. I won't fight back and increase my own trauma, and you'll be knock out before you can gut me."

"I'll take too much."

"That's why I have bone marrow, Janet. I'll recover."

"What if you don't? What if I kill you?"

He kissed her, having failed to find a worded explanation for his actions. She stiffened and started to draw away, but then relaxed and pushed herself so close to him, he could barely extricate his hands from her. But he only needed one, and it inexorably made its way towards the pocket where his knife was sheathed. The small part of Janet's mind that was still rational in spite of the kiss and the disease realized too late what he was doing.

Janet's eyes somehow remained sane and desperate for escape from her own body for a few minutes after the smell of Daniel's blood again filled the air. But then the madness and lust took them over and the temptation of blood became to great and she descended upon him again.

------------

"Why don't they attack each other?"

"What?"

"The Sanoctem, sir," Sam clarified. "Why don't they attack each other?"

Jack stopped pacing and looked back over the valley. They'd been walking almost four hours how, and the trail was starting to get really annoying. Daniel, it appeared, had been doing a lot of backtracking. Teal'c surmised that the erratic nature of the trail was not Daniel's attempt to throw off the tracking party, but concluded that Daniel was looking for something and was having trouble finding it. After the third dead end, Teal'c had tactfully suggested that he take the next one by himself. He fooled no one, and Jack let him go.

"I have no idea."

"But it doesn't make any sense, sir," Sam persisted. "Why would they risk attacking the Sandiem? Why wouldn't they just kill each other?"

"Moral code?" Sam glared at him. "I don't know, Carter. Crombie mentioned something about proteins while you were sending a message back to Hammond."

"Proteins."

"Yeah. When Aeronn told them about the 'treatment', Warner thought he meant a protein that was only found here."

Sam suddenly turned very green and the next thing Jack knew, she was on her knees and he was holding her head while she vomited. She wiped her mouth, horribly embarrassed, and took the water bottle when he offered it.

"Carter?"

"They drink blood, sir," she stated.

"I know that, Carter."

"What I mean, sir," she swallowed, her eyes bugging out slightly. "Is that the protein they need probably comes from the blood."

"And?"

"There's only one difference between the blood of a Sanoctem and the blood of a Sandiem. One protein is missing from the Sanoctem," Sam said thickly. "And Daniel didn't have it until after he was cured."

Jack was starting to feel a little sick himself.

"Do you think he knows, sir?"

"Oh, he knows all right," Jack said grimly and reached for his radio. "Teal'c? You there?"

"I am indeed, O'Neill."

"Any luck?"

"I believe I have located the cave."

"Perfect. Stay put. We'll be along shortly." Jack switched channels. "Sierra-Golf three niner, do you read?"

"Yes sir." Major Griff's voice buzzed.

"Griff, grab a medical team and get up here. Bring a lot of saline. And send someone back to the 'Gate with a message for Hammond and Warner. Tell them we're going to need a lot of whatever Daniel's blood type is standing by when we got home."

"Yes sir. What's going on up there?"

"I don't really have that kind of time right now, Major. I'll brief you get here."

"Yes sir. Over and out."

"Let's move, Carter."

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to be continued….