A/N: I realize that this story is sheer, shippy fluff, but I'm having so much fun with it, I won't even apologize! I categorized this as Angst/Romance, but so far, not so much angst, hey? Eh, I'm sure the mood will strike me later. (Can you hear my evil "Mwah-ah-ah!!" laugh?)

And, heck – if nothing else, you're probably getting a really good geology lesson!

Chapter 5

Sam pushed a few stray wisps of hair off her forehead. They'd been trudging down the south side of the mountain for nearly four hours now, and her calves were screaming with the unnatural movement. She supposed it was better than having to walk uphill, but not by much.

Glancing over at her CO, she noted the strained expression on his features with growing concern. Jack's knees pained him under the best of circumstances. Clearly, the rugged, downhill terrain did not qualify as anything close to "the best of circumstances," and it was starting to take its toll on him.

"Sir, do you want to take a break?" Sam knew she shouldn't feel guilty for worrying about his well-being. A comrade in distress would trouble any good soldier. However, there was a layer of emotion to her concern that would not have been present if the person in question was General Hammond or Teal'c, or pretty much anyone besides Jack.

To his credit, Jack didn't seem to become annoyed or suspicious by her question. "Nah. I'm good for another hour yet."

Sam, noticing his increasingly choppy movements, raised her eyebrows questioningly. "Are you sure? Because you're starting to look a little worse-for-the-wear."

Jack just shrugged. "You may be right, Carter. But if I sit down now, I'm not so sure I'll be able to get back up again. I think we'd better get as far away from the danger zone as humanly possible before my legs give out entirely."

Alarm shot through Sam's chest like a bullet. If her CO was actually admitting to his discomfort, then he was almost certainly in bad shape. "We can at least stop walking for a few minutes. I know my legs could use a quick breather."

Jack took in her ragged, sweaty appearance and nodded. As they stopped walking, he reached for his canteen and took a deep swallow.

Sam followed his example and then stopped to consider the mountain behind them. "Well, sir, the incline is gradually decreasing. We should be on nearly flat land within the next hour. Hopefully that will help your legs a bit." She tried to keep the edge of anxiety from her voice, but she knew she wasn't entirely successful.

Clearly picking up on her unease, Jack flashed her one of his devil-may-care grins. "Actually, that might just make it harder for you. I mean, if I fall over now, you'll at least be able to roll me downhill for a while, right?"

Sam suppressed a smile. "Good point. I guess if you wait to collapse on more level ground, I'll just have to leave you in the path of the lava flows."

He waved a finger at her. "C'mon Carter, you told me there weren't going to be lava flows with this kind of eruption."

Her eyebrows shot up in surprise. "You were actually listening?"

"Well," he said off-handedly, "I figured that since my life might actually depend on your boring science lecture, I ought to at least try to tune in." He shrugged. "Besides, I was really disappointed by that particular fact. I mean, what good is a volcano if there's no lava involved?"

Sam laughed. "Sir, there's lava involved, you just won't see it. When lava is below the surface of the ground, its called magma. And in this case, the magma is confined beneath hundreds of feet of rock. Eventually, that magma and all the gasses trapped inside it will build up enough pressure to blow the entire side of the mountain off. The explosion should be so violent that most of the magma will be blown high into the air along with tons of pulverized rock. That big, dark column of ash is called tephra. Anyway, the magma will cool almost instantly, falling to the ground with all the other debris in huge clouds of volcanic ash. We call such an event a Plinian eruption. It's one of the most violent expressions of tectonic activity ever witnessed by humans."

Jack couldn't help being absorbed by her speech, drawn in not by her words, but by the rapt expression on her face. The intense, faraway look in her eyes was so eager and unguarded, he had to suppress an affectionate smile. "Yeah, well," he said gruffly, trying to cover the warm feelings blooming in his chest, "I still say there should be lava."

Sam laughed aloud. "Actually, sir, I agree with you. The spectacular lava eruptions that we usually associate with volcanoes are much less destructive than plinian explosions. The Hawaiian volcanoes are a good example. People practically live on top of them, and it rarely causes anyone harm."

Enjoying the earnest, excited look on her face, Jack couldn't help egging her on. "Why is that, exactly?"

She had no idea why her CO was suddenly interested in the geology lesson, but she was thrilled to have his attention. "It has to do with the type of magma. Some of it is runny and easily flows to the surface. Generally, that kind of magma just bubbles up and runs down the mountain. Unless you're unlucky enough to be trapped in its path, you aren't in any danger." As she continued, she gestured to the peak behind her. "On the other hand, some magma is thicker and moves much more slowly. If erosion blocks the vents before the magma can escape, then pressure builds, and builds, and builds, until it finally explodes." She shrugged. "All that power trapped in one place… it eventually has to go somewhere."

As soon as the words left her mouth, Sam wished she could call them back. She could tell by the look on his face that they'd both had the same thought.

All that power trapped in one place… it eventually has to go somewhere.

Geothermal power wasn't the only kind of energy that adhered to that particular law of nature. They both knew that the intense attraction growing between them was bound to the same principle. Eventually, it had to go somewhere.

With their eyes locked, Sam could feel the heat of Jack's intense stare clear down to her toenails. "Maybe we should get moving again." Her voice was soft and obviously strained.

Jack was about to nod his agreement when suddenly the earth moved – literally.

A brief trembling beneath their feet quickly grew into a more pronounced shudder. It wasn't violent enough to knock either of them off-balance, but it was certainly sufficient to be alarming. "Whoa!" Jack instantly turned his gaze to the mountain behind them. There were no giant plumes of ash coming from the summit, so he assumed that nothing major had happened. Turning his attention back to his second-in-command, he looked at her intently. "Care to tell me just what the hell that was?"

Sam was relieved by the distraction. Then, of course, she realized that being relieved by a major seismic event in one's immediate vicinity was probably not a sign of good mental health.

Sighing inwardly, she set the feeling aside and concentrated on the matter at hand. "That was an earthquake, sir." Seeing the 'tell me something I don't know' look on her CO's face, she elaborated. "All right, here are the details. Volcanic eruptions are notoriously hard to predict, but there are a few things that we do know. As all that pressure builds beneath the surface, the rock above begins to shift. It's usually some kind of seismic event that starts an eruption. As the tectonic plates beneath the earth move, it forces that magma to the surface. Volcanoes are usually found along fault lines, so earthquakes and volcanoes go hand-in-hand." She took a deep breath before continuing. "Nobody is exactly sure why, but it's not uncommon for the number of phreatic explosions and earthquakes to diminish right before the big plinian eruption."

Jack raised his hands. "Slow down, Carter. What's a free-attic explosion?"

She nodded apologetically. "Sorry, sir. Phreatic explosions are those puffs of steam that Daniel and Teal'c saw rising from the mountain. There are usually hundreds of them before a big eruption. Anyway, you might expect to see lots more of those, along with a huge surge in the number of earthquakes right before the 'main event,' but that's not always the case. The three days before the eruption of Mount St. Helens in 1980 were the some of the quietest in months."

Jack still looked a bit puzzled. "So, if we're seeing these steam clouds and feeling tremors, does that mean we're safe for a while?"

Sam cringed. "Not at all, sir. In fact, I'm pretty worried. I'd have expected dozens of earthquakes and much more steam from an active volcano. I picked up a harmonic tremor on my seismograph within an hour of setting it up yesterday morning, but nothing since. Fact is, sir, things are quieting down. And I'm afraid that could signal time running out."

O'Neill absorbed the information and sighed deeply. "Well then, Carter, I guess we'd better keep moving."

She looked uncertainly at his knees, but nodded in spite of her concern. "Yes, sir."

Three hours later, Sam sat on the ground, eyeing her CO carefully. They'd discussed the location for a good camp rather extensively. Though they were fairly safe from major ash fallout and pyroclastic clouds on this side of the mountain, there was still plenty of concern about mudflows. When the water from the melting icecaps on the volcano rushed downhill, it carried with it a huge sediment load from all the falling rock and ash. The resulting flows were thick as concrete and fairly swift. At the base of the mountain, Sam knew that she and Jack would be mostly safe from the worst of it, but she still felt uncomfortable camping too near any streams or rivers. However, since fresh water was also necessary, they had to think of an alternative.

As they'd walked, Sam had scoured the aerial photographs taken by the UAV on its first flight, prior to their arrival on the planet. She'd just about given up hope of finding the perfect spot when she discovered something interesting.

Just beyond the active volcano lay another gently sloping hill. Though this hill was on the very edge of the photograph, Sam could barely make out on it a series of small pools connected by tiny streams. Since these streams were part of the drainage basin for the other hill, they would be clear of any mudflows from the volcano. Sam knew it was their best bet for a safe camp. Unfortunately, it was a good deal farther than she'd intended to walk, and Jack's legs had not help up well. The last hour trudging up the gentle hillside was spent in strained silence as her CO forced himself to move in spite of his pain.

They'd finally come to a clearing within sight of fresh water. Without ceremony, Jack had dumped his gear on the ground and collapsed in a heap.

Now, as she sat beside him, she felt anxiety bubbling up into her chest. He lay on his back with his eyes closed, obviously in pain.

"Sir?" she asked hesitantly, "Are you going to be all right?"

Jack spoke between clenched teeth. "At some point. Just not right now."

Sam bit her lip. "I'll get the tent set up. We'll move you inside and get you something for the pain, okay?"

He nodded wordlessly, which alarmed her even more. The fact that he wasn't trying to avoid pain medication gave her a good idea about the extent of his injuries. She sincerely hoped he hadn't damaged his knees any more than they already had been.

Without delay, Sam flew into action. She found a fairly level place for the tent and assembled it swiftly, laying their sleeping bags down inside. Then, she dug into her pack, looking for the first aid kit. After a few minutes of rummaging around, she realized it wasn't there. Jack must have rearranged things when he'd packed the gear dropped by the UAV.

She moved back to his location, trying not to dwell on how pale and drawn he looked. Gently stepping over him, she knelt beside his pack and unzipped it. Without a word, she began removing items, searching for the medical supplies that she knew were someplace inside. When her hand closed around a fairly large, rectangular box, she thought she must have finally found what she'd been looking for. Pulling it from the pack, she glanced at the container and froze instantly.

Jack had heard Carter's busy movement in the back of his mind. The red haze of pain radiating from his battered knees was distracting enough that he wasn't really paying attention to her activities. He knew she'd be able to get camp set up, and he'd taken comfort from the sound of her capable, swift actions. However, when her movement stopped abruptly, he opened his eyes and looked around with immediate concern.

Sam sat no more than two feet away, in the middle of a pile of items clearly pulled from his pack. She was still as a statue, a look of astonishment painted on her features. And in her hands, she held the jumbo box of condoms that Daniel had so thoughtfully provided.

Jack couldn't help it. In spite of the searing pain in his legs, he burst into peals of laughter.

She turned to him, still clearly stunned by her discovery. She obviously had no idea what to make of it. "Uh, sir?"

Getting hold of his amusement, he shook his head. "I can explain that," he said mildly. He opened his mouth to continue, but upon seeing the pointed look on her face, he closed it again. Smiling sheepishly, he shrugged. "Okay, so maybe I can't explain it." Chuckling, he pulled Daniel's note from his vest pocket and held it out to her.

Sam slowly set the box down on the ground and took the note from him. When she read the message, she turned bright red and closed her eyes in embarrassment. "Good grief," she muttered.

Unable to restrain himself, Jack started laughing again. "So Carter, I take it by the look on your face that those weren't what you were looking for in there?"

Still blushing furiously, she shook her head. Then, suddenly remembering what she had been looking for, she clapped a hand to her mouth. "Oh my gosh!" she gasped. "Sir, I'm so sorry. I was looking for the first aid kit!" She shoved Daniel's note into her pocket and resumed her search frantically, mentally berating herself the whole time. She knew that Jack was in excruciating pain, and she'd been so caught up in her embarrassment that she'd forgotten all about it.

Jack just smiled. His knees were still on fire, but Sam's innocent embarrassment had provided him with ample distraction for the moment. "Relax, Carter. It's in there. I'm not dying, you know."

Finally locating the box of medical supplies, she pulled it out with a flourish. "Still," she said breathlessly, "the sooner you get this medicine, the sooner you'll feel better."

He felt something tender grow in his chest at her words. She was truly one of the most considerate people he knew, always putting other people's well-being before her own. "So what did Janet send us?" he asked lightly, trying to squash his inappropriate feelings before they had a chance to hijack his good sense.

Sam opened the first aid kit and glanced inside. "We've got anti-inflammatories and pain killers." She looked at his knees uncertainly. "You really should take both. In fact, if you're in really bad shape, we can break out the morphine." There were an impressive number of the small vials in the box.

Jack shook his head. "Save it. We have no idea how long we'll be here, and we hardly have a great track record when it comes to off-world injuries."

Sam wanted to argue with him, but understood the grim logic behind his words. "All right." She pulled out two bottles of pills and shook one of each into her palm. "These should help. Take them, and once they start kicking in, we'll get you situated in the tent." She opened up her canteen and then held it and the tablets out to him.

He accepted them gratefully and pushed his upper body off the ground in order to swallow the pills. "Thanks, Carter." Handing her canteen back, he dropped back to his horizontal position and closed his eyes, waiting for the relief that would eventually creep in.

She recapped the container and looked down at him. The pain etched on his features was enough to make her heart constrict. She hated seeing anyone in pain, but it was especially difficult to see Jack this way. One of the things she relied upon most in life was his solid, unbreakable strength. It was frankly a little frightening when he was this vulnerable.

Sensing her mood, Jack searched for a way to ease her mind. Suddenly, he hit upon an idea. "Hey, Carter?" he asked without opening his eyes.

"Yes, sir?"

"You think we've got enough medical supplies to last our whole stay here?" He tried to sound appropriately worried, opening his eyes briefly to gauge her reaction.

Sam apparently bought his act, because she glanced at the first aid kit anxiously. "I hope so, sir. I guess it depends on how long we're stuck here, and how badly your knees are hurt. Why do you ask?" Looking back at him, she appeared so concerned that Jack almost felt bad for teasing her.

Almost.

"Well, Carter," he said seriously, "If we run out of pain medication, you're just going to have to break into the other box and think of an alternative way to take my mind off my knees…"

Seeing the scandalized look on her face, Jack couldn't stop himself from bursting into another round of laughter. He didn't even stop when he was suddenly bombarded by a giant, economy-sized box of condoms.

Within an hour of taking the first dose of medication, it had become apparent to both of them that one pain pill wasn't doing anything for his extreme discomfort, so he'd relented and taken a second one. Eventually, just after dusk, he'd felt enough relief to move into the tent. However, the effects of the narcotics had him a little off-balance. He'd needed to lean on Sam heavily on the short walk. Finally, though, he'd wound up on his sleeping bag, feeling significantly better than he had earlier in the evening.

Lying on his back, he looked up at the canvas ceiling. "Let's just hope Mount Doom doesn't blow until at least tomorrow," he said giddily.

Sam knelt on the floor beside him. Hearing the soft, gently-slurred quality to his words, she smiled in amusement. "Mount Doom?"

He nodded, returning her smile in the near-darkness. "Yeah, I figured you science types had come up with an appropriately dull name for it, like Volcano Number 41356 or something. And, since I refuse to be squashed under tons of rock from something called Volcano Number 41356, I decided to name it something better."

Sam chuckled. "Not a bad idea, but I think the name is already taken," she said, referring to the name's 'Lord of the Rings' origin.

"Who says there can't be two Mount Dooms? C'mon, Carter, let's name it after a classic." He shrugged. "In any event, maybe it will bring us good luck. After all, the good guys managed to escape in that story."

Filtered moonlight glowed through the canvas walls of the tent, reflecting off Jack's now-relaxed features. Sam couldn't help feeling a little breathless at the sight. There were few moments he truly let his guard down, but this, apparently, was one of them. The drugs had obviously done their job and then some. Absorbing his words, she felt a brief moment of anxiety. The characters in the story had indeed escaped unharmed, but certainly not unchanged. One of Tolkien's main themes was that it was impossible to regain lost innocence. Once something had happened, it couldn't unhappen. And, at that moment, Sam worried that her experiences on this volcano with Jack were going to make it impossible for them to return to their old lives.

Jack watched the expression on Sam's face change slowly from amused affection to worried sadness. Though his brain was too muddled to fully wrap itself around the implications of that change, he knew he didn't like seeing her upset. Reaching over to her, he grasped one of her hands in his. "Relax, Sam. We're gonna be fine."

She looked at his drowsy, earnest expression and she wished she could believe him. She tried to appear unworried, but simply couldn't pull it off.

Never taking his eyes off her, Jack suddenly tugged at her hand with enough force to pull her upper body down on top of his. Clearly not expecting the move, Sam landed on his chest with a soft "oof" One arm propped her up slightly, but her face was still mere inches from his.

In the dim light, he could see her eyes widen expressively. Releasing her hand, he reached up and cupped her chin gently. "Sam," he murmured softly, "You really do think too much."

And, with that, he pulled her face down to his and kissed her soundly.

A/N: More to come soon, I promise!