The boat zigzagged across the lake, water creaming under its hull as the wind filled the sails.

"Where are we going?" asked Lucy, looking back at Eden.

"An island in the middle of Avalon Water," Eden replied, as she steered the boat.

"The Isle of Avalon?" Lucy said, her eyes like saucers. "Is it magical?"

"It's Avalon Island," Eden said. "It's a normal island, but the largest one in the lake."

"It won't make us late for tea?" asked Lucy doubtfully, for Camden Palace ran on a tight schedule, and it had been drummed into Lucy from an early age that it was inconsiderate to the staff and other residents to be late for meals.

"What's today?" Eden asked, after a moment's thought.

"Tuesday."

"That's alright then," Eden said. "We have tea on the terrace every Wednesday, and Father's very strict about it. Any other day, I can come in whenever I like, as long as I'm there for dinner."

"Unless you're night fishing," Lucy said slyly, and Eden grinned in return.

The island soon came into view, appearing at first to be a miniature forest floating on the surface of the lake.

"How do we land?" Lucy asked, for below the trees a small cliff dropped to the water, and there were rocks around the island.

"There's a natural harbour on the other side," Eden said. "Keep a look out for rocks under the water".

"Rocks on the left hand side," Lucy called out.

"No landlubber talk," said Eden, steering away from the rocks. "The left side of the boat facing the bow is port, and the right is starboard."

"What if you're facing the other way?"

"Doesn't matter, it's always from the boat's point of view."

"That's much more sensible than left and right, where you have to ask if the person means their left or your left," Lucy remarked. "More rocks on the port side, captain."

In due course Eden brought Boudicca into a tiny bay on a pebbled beach which had a green willow on one side, overhanging the lake.

"Oh look!" cried Lucy, pointing. "It's a beautiful mermaid, dangling her long green tail in the water."

"You must have the blistering fantods," Eden said, after a glance at what she meant. "Sailors start seeing things when they haven't had enough sleep."

"I know it's not really," Lucy said. "But I'm sure this is a magical island, and there could be mermaids, if we only knew where to look for them."

"Stop talking bilge and help me with the sails," said Eden briskly. "Drop anchor, and I'll climb ashore and tie the painter to the willow."

Once both girls were onshore, Lucy asked if they were going to explore the island, because her feet were still bare, her sandals having been lost in the lake when she fell overboard.

"I brought you here to teach you to swim," Eden replied. "There's another beach through these hazel trees, and the path is sand, once you get past these pebbles."

The pebbles were an ordeal to bare feet, but the sandy track felt warm and soft to walk on. The hazel trees soon gave way to heather and bracken.

"I don't have a bathing dress to wear," Lucy said, when they arrived at the swimming beach -  another little bay, this one mostly sand, with only a few pebbles.

"Swim in your underthings. Or in nothing," Eden suggested. "You can't see this side of the island from the castle, it's hidden by the trees, and nobody ever comes here."

"Um, alright," said Lucy dubiously. "But you go in underthings as well, or I'll feel peculiar."

They both started stripping down, and Eden knitted her brows, saying, "Your underthings are far too fancy for swimming in the lake. Swim in nothing this time, and next time wear old underthings."

"These are old underthings," Lucy said, slightly self-consciously. "I've got an older sister, and she's very ... you see, Clarissa likes nice things and ... I think they give us both the same, so I won't feel left out."

"Oh," said Eden, removing her breeches reluctantly. "Well, I just have these. My nurse made them for me." She gestured down to her plain white calico vest, and knee-length knickers before dropping her breeches on the sand.

"They look so much more practical than silk and lace," Lucy said. "Your nurse is ever so clever at sewing, her stitching is so dainty."

Eden didn't reply, but led Lucy into the lake. They had to walk out quite a long way before they were waist deep.

"I'm a bit scared in water now," Lucy confessed, feeling sick the deeper the water got.

"That's why you're going to learn to swim," Eden said. "So you don't have to be frightened any more."

"I don't know if I'm ready," Lucy said tremulously. "I fell out of a boat only this morning."

"We won't start with swimming yet. I'm only going to teach you how to float."

Eden helped Lucy to lie back in the water, and supported her lightly as Lucy finally took her feet from the bottom, feeling as if the water was going to pull her down.

"Don't let go," Lucy said nervously.

"Even if I did, you can stand on your own feet here," Eden said. "Now, keep yourself nice and straight, with your shoulders back ... spread your arms and legs out wide ... don't forget to breathe."

Lucy tried to do everything Eden told her, looking up at the clear blue sky above, until she heard Eden say, "I took my hand away a while ago. You're floating on your own."

"It feels as if the water is holding me," Lucy said. 

"It is," Eden said. "Now, even if you fall out of the boat and can't swim yet, you know to lie on your back and float."

"For how long?"

"Until I come and get you," Eden said. "Now, are you ready for me to take you out to deeper water?"

Lucy had a fluttery feeling of panic as Eden dragged her by her hands out of her depth, but once she took her hands away, Lucy realised she was still floating. No matter how deep the water, she could spread out like a starfish, and lie as comfortably on the lake as if she was in her own bed.

The cool water tugged gently at Lucy's limbs, the sun shone, a light breeze wafted over her face. She felt as if she could drift like this forever. She was almost swimming, and she never had to be afraid of falling into water again.