The moment they hit the aetherosphere, Rue fell instantly and entirely in love with her new ship. They crossed into the blurry nothingness of aether, losing sight of both the world below and the sky above. It was a great scientific mystery that the aetherosphere was invisible, except when one was inside it. And inside was a treacherous space to be. However, Rue’s ship took to the currents with such grace it was almost as though they were still floating in normal air.

Percy was equally charmed. “This is what she was made for. Goodness, feel her go.” His self-importance gave way before a misspent youth tagging after Rue and Prim as the girls took Dandelion Fluff Upon a Spoon out for yet another illegal jaunt. Percy might be a bluestocking but he did love to float. It was one of the reasons he took Rue’s job offer.

The Custard slid smoothly through the aether where any other ship would have shuddered and jolted. Percy examined the Mandenall Pudding Probe’s dial. It was set for the Gibraltar Loop but the first hop into a current was always the hardest. The moment they entered the aetherosphere they began drifting with the local idles southward.

“Take us up, please,” said Rue.

Percy pressed down hard on the puffer button to put a little more rise into the balloon, and they glided up and began drifting east.

“And again, please,” ordered his captain. Rue was enjoying command. Especially over Percy. “This time, bring her nose around to the south.”

Percy puffed the Custard up once more and engaged the propeller to maximum. It farted loudly and they started a slow spin. At that moment, the Mandenall emitted a squirt of viscous milky liquid, not unlike rice pudding. This was how it had earned it its name. This was also the only sign they would get that they were directly below the correct current.

“There she is – the Gibraltar Loop,” crowed Rue. “Hop it, Professor Tunstell, on my mark. And… mark.”

Percy engaged the puffer once more and the ship rose up, hooked into the current, and began drifting.

Rue grinned in pleasure. “That’s our lift – let’s button it down.”

Percy went into a flurry of dialling things to the correct places and cutting all steam power to the propeller.

Rue called out to the deckhands to raise the mainsail and the Custard came about beautifully, hauling fully to sit entirely within the Gibraltar Loop.

They all held their breath, hoping that they had settled into the correct side of the Loop – the one that went towards Gibraltar rather than away from it. The probe could tell them the right current but not whether it was heading in the right direction.

Percy checked his compass.

“Steady on course, captain – floating the Gibraltar southbound,” he crowed.

“Next hop?” Rue wasn’t about to let him glory in his accomplishments for too long.