The water instantly stopped flowing past her, and instead began to build up in the trough and then started to overflow it, rising up to the level of the stone lip of the aqueduct. Some of the water spilled over the sides to fall to the ground below, but she caught most of it, allowing the water to rise to fill the aqueduct to the brim for twenty, then thirty, then sixty yards behind her. The weight of all that water was immense, and Isana could feel Rill begin to strain. She waited until the pressure of the dammed stream rose to Rill's breaking point, and then she lifted her right arm, palm up, and opened a way for the water to escape- not forward and down the stream, as before, but arching up to one side, toward the roof of the Grey Tower.
The water shot forth in a geyser, rising in a beautiful arch that reflected starlight and the gleam of the many-colored furylamps of Alera Imperia. For a second, a ghost of a breeze pressed against the stream, and it fell short of the roof-but the breeze died again, and a steady spray of cold water splattered down onto the stone roof of the Grey Tower.
Isana felt a fierce smile stretch her lips, and she remained locked in that position, joined with Rill, sending the waters of the aqueduct rushing over the stone of the Tower, rapidly spreading and filling the parapet with a shallow layer of water.
"There!" Isana gasped. "Kitai, do it now!"
Kitai stepped forward, crouching down at Isana's feet, and with one gloved hand she drew from the heavy little sack one of the coldstones they had stolen the night before. She placed it on the floor of the aqueduct, just upstream of the point where the waters arched up to leap to the roof of the Tower, held it there with her gloved hand, and with the other swung the steel hammer sharply down.
There was a deafening crack and a flash of cold blue light, as the fire fury bound within the coldstone greedily sucked the warmth from the world around it.
Coldstones were expensive works of crafting, containing fire furies far more powerful than those found in furylamps or those used to manage the heat of a kitchen's stove and oven. They were specially bound, and though created to draw in all the heat they possibly could, the bindings placed upon them prevented them from pulling more than a tiny trickle into themselves at any one time. The result was a stone that leeched the heat from everything around it over the course of three or four months-the limit of the stone's construction. Placed in an insulated storage box, a coldstone could keep food placed inside it well chilled, even preserve ice over the course of a hot summer.
But in shattering the stone to which the fire fury was bound, Kitai had loosed it to sate its hunger for warmth in a single, unbelievably frigid instant.
The blue fire of the loosed fury's hunger lashed out through the water in a wave of chilly light. Rill and Isana prevented the cold from rushing back up the stream, and instead it followed the course of least resistance, leaping through the arch of water, freezing it to solid in an instant. The wave of frozen blue fire crashed down onto the surface of the Tower and spread out through it in a glittering haze, freezing the water there into a rough-surfaced sheet of ice.
Kitai let out a whoop of excitement and raised a triumphant fist. Isana, shaking with weariness, released the aqueduct's current, which immediately resumed its course in a surge that gradually began to sink back to its original levels. Her foot slipped, and she almost fell, but Rill swirled around her before she could, supporting Isana and helping her regain her balance. For a moment, the fury appeared in the only physical form Isana had seen it take, the shape of a face-a mirror of Isana's own features, when she'd first bonded with Rill as a gawky, thirteen-year-old girl-that appeared on the surface of the stream, smiled, then vanished once more.
Isana stepped wearily out of the water, her skirts soaked from her near fall, and stood beside Kitai. "Now what?" she asked. Her voice sounded rough, even to her own ears.
Kitai gave her a pensive glance, returned her attention to the building, then down to the grounds below, her gaze roaming warily. She reached into her case of coiled lines again and began taking them out. "We wait here. Once they come out on the roof, I'll throw them the lines, and they'll swing over, just as I did with you. Then we meet Ehren."
"What if..." Isana shook her head. "What if they're caught?"
Kitai frowned, her hands moving swiftly and steadily, preparing the lines, her eyes everywhere. "They are not caught yet."
"How can you know that?"
She touched one hand briefly to her chest. "I feel him. Excitement. Fear. Determination. Had he been captured, he would immediately begin blaming himself for failure."
Isana blinked at Kitai. "You know him well, don't you?" she murmured. Then Isana gave the younger woman a thoughtful and rather whimsical smile. "This must be what it feels like when I tell others without watercraft what it is like to sense other people's emotions."
"It doesn't feel the same at all," Kitai said absently. "With him, it is more nebulous, but... deeper, somehow. The emotions of others are flat, like a painting, perhaps. His are more rounded, like a sculpture."
Isana frowned over her words for a moment, then caught a sudden flash of emotion from Kitai-realization and chagrin. She turned to stare at the Marat woman. "Kitai," she said. "How could you possibly know that?"
Kitai stared at her, frozen for a heartbeat, her green eyes wide. Then she turned back to her tasks, biting her lower lip.
Isana stared at her in dawning comprehension. "How could you know the difference unless you'd felt it yourself," she murmured. "Watercraft. Kitai..."
"Quiet," Kitai said, her voice flat with worry, and nodded to the arched column of ice stretching to the Tower. "Someone will see that soon. Don't make it easy for them to find us and shoot us."
Isana would have been choked silent by the implications in any case. No Marat had ever used furycraft. No Marat could. And yet if Kitai truly had knowledge of watercrafting, it meant that she, alone of her people, could wield power through Aleran furies.
Kitai was the only Marat ever to form a bond with an Aleran, and that bonding, Isana knew, somehow shared portions of each being in it with the other. Walker, the gargant bonded to Doroga, Kitai's father, was uncommonly intelligent for a simple beast, and seemed to understand Doroga implicitly. Doroga himself was taller and more heavily laden with muscle than the Marat from the other clans, and Isana knew him to be almost unbelievably strong.
If his daughter had bonded with Tavi in a similar way, then her furycraft could only be the result of that bond.