Tris did not run - she was too fat, and it would be silly to reach the wall only to be too winded to climb to the top. She walked - quickly - because her friends might just follow. Tramping through the grass beside the wall, she worked her feelings to a fever pitch: emotions were the key to her power to damage things, weren't they? She remembered the look on her parents' faces, when they told a perfect stranger at Stone Circle Temple that they no longer wanted her. She remembered Uraelle taking her books when the chores weren't done as well as she demanded, and dormitory girls taunting her about her looks. She remember Winding Circle boys who called her "fatty", and made pig noises at her.

The winds came to her, whipping her clothes and wrestling the lightning for her hair. They tugged her this way and that as she mounted the stairs a few hundred yards from the South Gate.

"Get out of here!" cried a guard, running towards her. "It's not safe -"

A billow of wind struck his chest, knocking him down. "Stay back," Tris warned. "I don't want to hurt you."

He got up, and advanced. She sent the wind at him again, strengthening it. Knocking him down a second time, it pinned him to the wall. Glancing to either side, Tris saw more guards take notice; they were coming to their comrade's help.

Behind them, further down the wall, mages were looking to see what the trouble was.

She had to keep everyone off her. Using winds on them cost her little; she only needed a dab of magic to send them where she wanted, since the winds were already here. Working them was distracting, though, and she couldn't afford distractions.

Once Niko had told the four that, when things were difficult, they could open their minds and let the magic guide them. Tris did so now, looking to see how she could work uninterrupted.

The image of a circle bloomed against her closed eyelids. Rosethorn and Lark had created magical circles before, to keep magic in. Who was to say they couldn't be used to keep people out?

She dragged her fingers through her hair, collecting a palm-full of sparks. A quick glance around told her the mages were now advancing with the guards. Swiftly she worked the sparks with her free hand, ignoring the needle-like pricks the bits of lightning gave her as she shaped them. Pointing to the walkway before her with the hand that held the ball of sparks, Tris began to turn, drawing a circle in lightning. Its fire streamed down, burning where she placed it, until she closed the circle. She was now fully enclosed, with a good two feet of room on either side. Twitching her fingers, she raised the fiery circle until it made a wall over five feet high at her back and sides: before her lay the top of the wall and the cove. Now she could get to work.

Tris grabbed two fistfuls of wind. She twisted them around each other, following the lessons taught by Lark and Sandry: spinning makes weak fibres into strong thread. Finished, she backed up to the inner edge of her lightning-circle, and stood her wind-thread at its centre. Grimly, she twirled her finger clockwise. The wind began to whirl.

Bit by bit it drew in pieces of other winds, growing taller and wider. When it was of a size to crowd Tris out of the circle, she guided it into the air, and let it touch down in the blanket of thorns on the other side of the wall. Twigs and sticks fought their way up the growing funnel as it ate vines to give it a thorny kind of armour.

Once before Tris had fought, and failed, to make a water-funnel do as she wanted, and it had been only ten feet tall. When her cyclone towered thirty feet in the air, higher than the wall on which she stood, she urged it up, out of the brambles. Making shooing motions with her hands, she sent it forward.

The moment it entered the sea, the funnel inhaled, to become a waterspout. It widened and continued to grow as it bore down on the pirate fleet. Ten yards or so from the closest galley, the waterspout struck the pirates' magical barrier, and stopped.

"Aymery," she growled to make herself angrier, and slammed her creation forward. It sprayed against the glass-like wall, grinding at it. "Aymery, and the carpenters, and your poor slaves." Again and again she threw her creation at the barrier, without result.

"Now you know why you need us." Sandry walked through the lightning-wall to stare reproachfully at Tris. "You should have waited."

Soldiers and mages were clustered at a respectful distance from Tris's fiery hideout. It was easy for the other three to see those who had gone closest to it: their hair stood on end. Daja nodded gravely to them as she and Briar followed Sandry through the lightning.

Tris stared at her friends, baffled. "It didn't hurt you?"

"It stings," said Daja, rubbing her arms.

Briar took a place at Tris's side. "You can't pound pirates without us," he told her. "It wouldn't be as much fun."

"They'll know we're gone soon," pointed out Sandry. All four knew who 'they' were. "We need more than this circle to keep them from stopping us."

"This was the best I could do." Tris sent more winds out to help the waterspout, and smiled as the funnel got longer and fatter still.

"But we can do better," Sandry informed her. "Why not take this circle up, and I'll weave us a new one?"

"New one first," said Daja. "Then break the old one. Otherwise those guards outside will grab us."

Sandry nodded. Laying her palms flat against the lightning barrier, ignoring the pain as its fire bit into her skin, she searched her mind for the wall that had kept them safe at the North Gate. Thread by thread she wove it against the lightning's surface, her magic shuttling faster than the eye could follow. Her barrier rose around the four, holding the same shape as the lightning wall.