The group was very happy to be away from the volcano, especially when the ground smoothed and the cart stopped jostling. Fluttershy had helped pull the cart today, partially because she wanted to put as much distance as possible between herself and the dragon, and partially because she wanted to spend some time alone with Kai.
"Thanks for not dragging me up the mountain," she said as they stepped out of the crags into open prairie. "I really didn't want to see that dragon."
"Think nothing of it," said Kai, nuzzling her. "If it were me, I'm sure you would have done the same. In fact, you have."
Fluttershy blushed. "That was different. I wanted to do something nice for you."
"And I wanted to do something nice for you. That's why I didn't make you go."
Fluttershy smiled. "You're sweet." Thinking back on how they'd first met, she'd have never imagined that she'd be having a civil conversation with him, much less having a romantic interest in him. She wished they could explore further, but this was good enough for now.
They made a goodly amount of progress today, coming to rest at the edge of a forest. With camp fully set up, Fluttershy reached into the back of the cart and pulled out the washboard and basin. While Kai and Nik had been busy on the mountaintop, she'd finished making new clothes for Nik, and it was time to wash them for him. Just as she was ducking behind a tent to fill up the basin from a nearby pond, she noticed Kai's cloak draped over the wagon's yoke. Having slept underneath it a few times, she knew it was in need of a good cleaning. With a quick swipe, she added it to the laundry. She thought it would be nice to surprise him with a nice, clean cloak.
Twilight sat down next to Kai in front of the fire. "Hey, Kai, do you know what Sky was talking about with this wavelength amplification? I can't make heads or tails of it."
"It's a way to use spells of higher power without changing their resonant frequency."
"How does that work?"
Kai tossed another log on the fire. "I'll show you. Cast a light spell, and I'll amplify it for you."
Twilight put on her light as directed. It illuminated the local area, just extending beyond the edge of the camp. A low rumble came from Kai's chest, increasing in volume as he opened his mouth. As his pitch shifted slightly, Twilight's horn began to grow brighter until the light reached the trees. Thinking he might be able to increase it even further, Nik tried to match the frequency Kai was putting out with his own voice. He was a little off, but he managed to increase the range a meter or so regardless. As the sound faded away, so did the light.
"Wow," said Twilight, looking back at the documents. "How do you know what note you're supposed to hit in order to increase the efficacy of the spell?"
Kai returned to preparing their dinner. "Some of it comes from experience. If you work with it often enough, you learn to feel it. That said, it's a lot easier if you can feel the flow of magical energy."
"And how do you do that?"
Kai looked up and blinked a few times. "You know, I've never tried to put it into words before. I always just sort of... felt it."
"Not all unicorns can just 'feel it,'" grumbled Twilight. "In fact, I'd wager that most unicorns can't feel it, otherwise, there'd be more literature on the subject."
Kai nodded. He'd only recently begun to read more current books, but only rarely did they mention feeling the magic flowing through you. Most of his training in doing so came from Sky, in fact. "Give me a moment," he said, standing up. "I'll be right back."
After a few moments, he came back, a flat, oval stone disk in his grasp. He sat down next to Twilight and started mucking with the rock. "What's that for?" asked Twilight.
"Magical ley lines run all throughout Equestria," explained Kai. "They're far enough underground that by the time they emanate their magic up to the surface, it's all been spread out and diluted to the point where most ponies can't tell where the highest concentrations are, or the lowest. To them, it just seems that they can cast their spells wherever and whenever." Having chiseled a hole into the center of the stone, Kai held it up to his eye, then draped it over his horn, pumping a bit of magic through it. "Given the right training, anypony can learn to feel the flow, not just unicorns." With another look through the hole in the stone, he passed it to Twilight.
Twilight was suspicious about what she'd see through the stone. Still, she was curious. She held it up and looked through. Within a meter, there was nothing, but outside of that range, she could see little pink threads wafting up from the ground. Half of them went in one direction, the other went in another, crossing each other as they went. There was a very faint glow in the distance, far underground. Several thousands of the tiny threads emanated in all directions away from it. "What exactly is this?" she asked.
Rather than answer right away, Kai took a few steps away and cast a simple levitation spell. Several threads clustered together, crossing at his horn and at the pan he was holding, a bright white stream connecting the two knots. "What you're seeing is the flow of magical energy." He waved his hoof through the stream of magic, and it danced around him. "Between my horn and the pan are countless tiny threads, right? They're all vibrating at the same rate. If you were to vibrate your vocal chords at the same frequency, you could potentially double the amount of energy flowing through it, making all of my movements much more powerful."
Twilight was in awe as Kai hung the pan back on the rack. She thought herself smart, but she had to remind herself that even the wisest ponies could not know everything. Still, having learned something new today was a good step forward.
Fluttershy, done with the laundry, flapped her way over the tents. "Hey, guys. Are you having a nice conversation?"
Twilight's jaw dropped when Fluttershy came into view. The pink threads twisting into white knots indicating the use of magic were flowing through her wings with every flap.