Sophronia, on the other hand, felt self-conscious. She stuck out like a puff pastry among meat pies in her prim dress. She was glad that when they stopped it was behind a massive rotary engine to one side of the room, mostly out of sight.

Vieve grabbed an impish towheaded boy by one elbow. “Rafe, fetch Soap, would ya?”

“Do it yourself, Trouble.”

“Can’t. I got important company. Couldn’t leave a lady alone in this dangerous place, now could I?”

“Her?” The blond boy squinted into the shadows where Sophronia stood. “What’s one of them doing down ’ere?”

“Same as everybody else: minding her own business. Now get Soap, would ya?”

The blond sniffed, but ambled off.

“Pleasant young man,” commented Sophronia.

“They can’t all be as charming as me,” Vieve replied with a smile.

“Or as adorable as me,” added Soap, coming up behind Vieve and nicking her cap. “Good evening, Miss Temminnick; Vieve. To what do we owe this honor? Shouldn’t you be watching a play or something highfalutin in town?”

“Give it back!” Vieve made a grab for her hat, but Soap held it out of reach. “Can’t stand the theater.”

“And I’m not allowed,” Sophronia added. “But Soap, Vieve and I were wondering if you could help us get out?”

“Out?”

“We want to pay a visit to Bunson’s.”

“But why? No one will be there.”

“Exactly,” crowed Vieve.

“They’ve got something we want to see.”

Soap was suspicious. “What kind of something?”

“A communication machine,” Sophronia explained.

Vieve nodded, grinning.

Soap looked back and forth between them. He ended with Sophronia. “Not you as well? Gone barmy over mechanics, have you? I should never have introduced you two. It’ll all end in tears and oil.”

“Not really. I’m more intrigued by this one’s desirability.”

“What?”

“Flywaymen want it, or parts of it. Monique failed because of it. I’ve seen two air battles so far over stray bits of it.”

Soap latched on to the last part of her statement. “You saw what happened with the mid-balloon?”

“Yes, and I saw you repairing it.”

“No joke. I was squeaking for nigh on an hour because of all that helium. Funniest thing, repairs up top. So?”

“Someone fired a cannon at us.”

“Because of this communication machine?”

“Not exactly. Because of a piece that might make the communication machines actually communicate with each other.”

Soap looked confused but willing to play along. “Well, very good, then, but I better come with you. Can’t have you two scrabbling about groundside unsupervised.”

Sophronia arched her eyebrows. “I assure you, I have been sneaking around with impunity for years.”

Soap glowered at her.

“Oh, very well,” said Sophronia, unwilling to waste any more time.

Soap enlisted a few off-duty sooties so that a small, dirty herd escorted Sophronia and Vieve over to yet another hatch in the boiler room floor. This was one Sophronia hadn’t noticed before, in a corner behind what she assumed was a hot water pump for the school’s serpentine room-heating system. Up top, in the residential rooms, the heating contraptions looked like grates in the walls, and they kicked in at night if it got icy, which it often did up high. The one in Dimity and Sophronia’s room made such a rumbling and growling that Dimity named it “Boris the Indigestive.” This, then, was Boris’s origin.

There was a coiled rope ladder resting nearby. When the hatch flipped open, it became clear the airship was floating very low to the ground, perhaps only two stories up. They were also at the edge of the moor. Swiffle-on-Exe became visible after they let down the ladder and began to climb.

The school had stopped above a knoll off a goat path above the town, but it was far enough outside the village for Sophronia to be nervous that, should the moor mists rise up, they would not be able to find their way back. The moon was full, which explained both the revels in the town and the absence of Captain Niall. He would be a true monster tonight, uncontrolled and uncontrollable. Sidheag had explained that Captain Niall took himself off several days before the moon, far into the moor, away from civilization, so that his moon-mad werewolf self wouldn’t be a danger to anyone. Sophronia thought this sad. Werewolves supposedly loved the theater.

They dropped down to the grass, Sophronia first, then Vieve, and then Soap. Soap saluted the sooties above and the ladder was pulled up. They would lower it again in exactly two hours, right before the performance was supposed to let out. Sophronia worried about the time constraint, but Vieve was confident that two hours was enough.

Under the bright moon, the path into town was well-lit. Swiffle-on-Exe was a silvery hodgepodge of thatched roofs, church steeples, and the looming monstrosity of Bunson’s to the left. They moved at a swift trot and arrived at the gates to the boys’ school in a little under a quarter of an hour.

Sophronia hid while Soap pulled the porter’s bell rope. They had decided to let Vieve face the porter mechanical initially, both because she had the obstructor and to ascertain whether the porter would recognize her as a female. Vieve maintained that the identifier nodule apixiter, whatever that was, had to be the shape of the lower half of a human body and that if Sophronia would only don trousers like a sensible person…

Either Vieve was correct or some other aspect of her personality came off as intrinsically masculine, for when the gate was thrown open and the mechanical stood facing her, he made no objection.

Vieve stepped toward him and puffed up her chest. “Message for Mr. Algonquin Shrimpdittle from Professor Lefoux,” she said in her high treble voice.

“Give to me, young sir,” boomed back the porter from behind his faceless confusion of gears and cogs.

“Can’t be done,” replied Vieve. “Orders are to deliver it directly.”

The porter let out a blast of steam in apparent annoyance. This flapped up the cravat pinned about his neck so that it momentarily obscured his clockwork face. He whirred and clunked, sending out a puff of smoke from a stack at the top of his head. Finally he said, “Very good, sir, follow me.”

The porter made a wide loop on its tracks. It hadn’t the pivot mechanism and nimbleness of the single-track mechanicals on board the finishing school. It began to trundle away, the wheelbarrow on its backside rattling side to side.

Vieve turned to Sophronia and whispered, “Go on! Hop in!”

“What, inside?”

“It hasn’t any sensory nodules on its back.”

Sophronia gave the young girl a look of doubt. Then again, Vieve was correct about the porter not recognizing that she was a girl. She exchanged a look with Soap.

The tall boy flapped his hands slightly in the universal gesture of “you decide.”

Sophronia shrugged, jogged after the porter, and, with a flutter of skirts, hoisted herself inside the wheelbarrow. Soap sprinted after and jumped nimbly in next to her. He sidled in close, bumping up against her shoulder, and grinned. He smelled of soot. Sophronia thought it rather a pleasant odor, on him, and smiled back. Genevieve Lefoux was correct—the porter didn’t register their presence.

Vieve walked alongside the mechanical, as though they were companions out for a stroll. It was rather comical, given that the porter was easily twice the young girl’s height and three times her girth.

The mechanical’s tracks ended at the front of the school’s main building.

This was far more the kind of structure Sophronia had expected from Mademoiselle Geraldine’s Finishing Academy for Young Ladies of Quality. Bunson’s had an impressive staircase leading up to huge double doors of wood and iron, engraved with an intricate pattern. Sophronia crouched low in the wheelbarrow as the porter mechanical approached the steps. How will he alert the interior as to the presence of a messenger?

The porter touched up against the bottom step where his tracks stopped. This triggered a response. A tremendous amount of steam emanated from below the lowest step, and with a great creaking and groaning, the stairs closed in upon themselves. The whole front section of the building that housed the main doors compressed downward like a concertina. After only a few moments, the doors were at ground level and the stairs had flattened out in such a way that it allowed the porter’s tracks to continue.

The porter proceeded toward the doors sedately and bumped autocratically against them with a clang. This was obviously a signal, for one of the doors opened, revealing a darkened corridor. The porter backed off of the collapsed stairs far enough to switch tracks, beginning another loop that would lead him away to commence a circuit of the grounds. As he did this, Sophronia jumped out. She dashed inside, flattening herself instantly on the back side of the unopened half of the door. One never knows who might be watching.

Soap and Vieve followed sedately after.

As she passed through the doors, Sophronia noted that the intricate pattern carved into them was that of multiple octopuses holding one another’s tentacles in a long unending chain.

It was a good thing she’d chosen stealth, for on the other side of that door a new set of tracks started up, and waiting patiently was yet another faceless mechanical, this one smaller, wearing a white ruffled pinafore, and carrying a duster in its articulated forceps. It was different, more chunky-looking, than the maid mechanicals at Mademoiselle Geraldine’s. This maid said nothing and did not react to Sophronia. Sophronia hoped that meant the creature could not make her out in the shadows.

Close on her heels, Vieve and Soap crowded in, intent upon coming to her rescue, if necessary, or her disguise, if not. They saw her hiding and confronted the mechanical maid, both talking at once and gesticulating wildly.

Sophronia hoped that this would confuse the sensory nodules Vieve had referred to earlier and took it as permission to inch past the maid and run down the hallway. Soap and Vieve followed.

They paused for a breather on a small staircase to one side of the hall.

Behind them, the front foyer of the building raised itself back up, filling with white steam as it did so.

“You should have worn trousers,” said Vieve in a low but disgusted voice.

“I may not be a lady yet, by any account,” said Sophronia with great dignity, she felt, “but I am not a boy, either!” She was finding herself far more concerned with attire now than before attending Mademoiselle Geraldine’s.

Soap looked at her. “You look like a lady to me.”

“Thank you, Soap.” Thank goodness it is dark enough for him not to see me blushing!

“Of course, miss.”

They continued down the next corridor.

There seemed to be fewer maids at Bunson’s, or perhaps they were decommissioned while the students were out. Sophronia would have predicted that a school full of boys would require more maids, not fewer! Everything was going swimmingly, with Vieve leading them unerringly ever upward though the building.

“You’ve been here before?” whispered Sophronia.

“Many times. Auntie always has some matter to discuss with Mr. Shrimpdittle. Lady Linette won’t let her leave me unsupervised on board. She used to try to get Mademoiselle Geraldine to mind me, but I’d always escape her.”

“So you’ve seen the communication machine?”

“Not as yet. They leave me outside. ‘Workshop’s no place for a child.’ ” Vieve’s voice was full of outrage as she repeated a phase she had clearly heard overmuch in her nine years. “But I know where it’s kept. On the roof.”

Both Soap and Sophronia paused, raising their voices in shock. “The roof?”

“Shush! We don’t know who might not have attended the theater. They wouldn’t leave the school with only mechanicals on duty.” Vieve took a moment to roll up the long sleeves of her shirt, her exposed wrists small and bony.

Sophronia said, “But why stash a piece of delicate equipment on the roof?”

“Search me. Intriguing, isn’t it?” Vieve dimpled at them in a way that made her look very young indeed.

We are being led into enemy territory by a child, thought Sophronia all of a sudden. This is madness. Oh, well.

At that moment, a door ahead of them opened out into the darkened hall. Bright unflickering light of the kind that could only come from high-quality gas spilled forth. Into the beam trod a dark blob of a boy—not a mechanical.

The boy was relatively stocky and, like Vieve, shrouded in clothing too big for him. He was bent over a large, antiquated book and humming to himself.

Sophronia, Soap, and Vieve froze in horror.