Ark didn’t answer, still dazed with their success. Was it the feather or had he done it himself? And how had the Warden known? He still couldn’t believe it. Arktorious Malikum, foundling son of a sewage worker, briefly invisible!

“Weird … It’s like I was curled up in me gran’s lap, there.” Mucum shook his head as if to get rid of any remaining soppiness. “Don’t ever tell anyone I said that, right?”

“Whatever.” Ark suddenly thought about his sister, Shiv, throwing sticks off the edge. The image of her little grubby smile was almost too much. Would he ever see her again? But her playful throwing game had given him an idea. There was only one place safe to hide. One place they’d never think of looking. Down. Ark stood up and squeezed past Mucum’s bulk to reach the other porthole.

That single moment of quiet had filled Ark with certainty. He was already turning the wheel. This second valve was well greased and the door opened easily. The smell hit them first. It was the opposite of work — sweet, fresh, hinting at treetop meadows and the hundreds of cruck wells, natural hot baths, springs, and meandering branch tributaries that fed Dendran dwellings high in the canopy as well as filling the leaves with liquid life.

Mucum pushed in beside him to stare at the huge, dark shaft at least thirty feet across that vanished into the hollow depths of the trunk, lit by a string of feeble, flickering gas lamps. “You must be kidding, Malikum! This ain’t no place for the likes of us!”

Below them, a series of rusty metal rungs descended into the gloom.

“We’ll be fine….”

“No, we won’t!” Mucum unwittingly crossed himself. “It’s another country down there!”

“Exactly. The guards will never follow us.”

“Save us from acorn nutters! The guards won’t follow us ‘cos they fancy still being alive in the mornin’, unlike you, Mr. Holly High ‘n’ Mighty!” Mucum craned his head up, trying to make out various outflows that ran off the main shaft, empty at this moment, waiting for the tide to turn.

“We’ve got plenty of time,” said Ark. But the certainty was beginning to fade.

“Oh, so yer suddenly the expert, eh? I don’t see yer tide tables!”

“I know what I’m doing.”

“Like you did with the King? That little swim has left your brain full of doo-doos! You’ve forgotten yer basic trainin’! Turn on the tap and what do yer get? Water! Where’s it come from?”

“The day that you teach me anything …,” said Ark as he grabbed hold of the first rung and swung his legs over the side.