He received sounds of confirmation from Burton and Swinburne.

“The immense calculating power of the helmets,” Gooch went on, “is made possible by an inconceivably complex electromagnetic pattern existing within the diamond dust; a pattern that employed Edward Oxford’s mind as its template. When he was killed by El Yezdi in 1840, his terminal emanation—a powerful burst of energy from the brain—instantly overwrote it, but since this matched what was already there, there was no untoward effect.” He stood back. “The damaged suit didn’t fare so well. Its electrical composition was already badly impaired by prolonged exposure to the madness of the Oxford who’d become known as Spring Heeled Jack, and when he died, whatever vestiges of sanity that remained in it were erased by his last mental gasp.”

Passing back along the side of the bench, Gooch reached out and picked up the helmet. “This is a truly remarkable machine. It can enter a state called ‘self-repair mode,’ which allows its internal components to alter their function in order to carry out whatever maintenance is necessary. Had we, like the other histories, only the one ruined suit, we would have rerouted what power remained in its Nimtz generator to the headpiece, hoping that somehow, in its insanity, there was retained sufficient an instinct for self-preservation to instigate repairs. Perhaps it would have somehow reordered its synthetic intelligence.” He turned the helmet in his hands. “But we were lucky. We had this pristine version, which is why Mr. Babbage created that—” He jerked his chin toward the box-like affair. “A Field Amplifier.”

Burton swayed slightly, in the grip of a synaesthesia that suddenly made the sound of Gooch’s voice a floral scent, turned the scene before him into a symphony of visceral sensations, and transformed the oily odour of the workshop into a melodious purring. He glanced at the glowing tip of his cigar. It was a miniature sun.

“With it,” Gooch went on, “we intended to record the electrical pattern present in this helmet and copy it across to the defective one, replacing the insanity therein.”

“Marvellous!” Swinburne exclaimed. “What went wrong?”

“Charles has a curious sense of occasion. To him, every event is a mathematical formula and its every possible outcome an elaboration of the calculation. Applying this hypothesis to the suits, he proposes that they manipulate a single great equation—a stupendous envisioning of time’s structures and processes—and that by observing coincidences and sequences, he might one day comprehend it. This is why today’s anniversary was significant, and why he initiated the experiment at exactly nine o’clock.”

Charles Babbage suddenly came out of his self-absorption, stepped forward, and slapped a hand down onto the worktop. “The synthetic intelligence is responsive, not active. I could not have issued the command independently.”

A particularly violent bolt of lightning whipped through one of the overhanging globes. The crackling detonations echoed around the massive hall, and the white light momentarily illuminated the normally shadowed sockets of the scientist’s eyes, revealing a fanatical glint within.

Burton felt the inexplicable suspicion that, rather than being present in Battersea Power Station, he was somewhere entirely different.

From afar, he heard Swinburne cry out, “Command? What command? My hat! In all the many histories, is there a single Charles Babbage who can get to the confounded point?”

As the king’s agent splintered into innumerable renditions of himself, Gooch said, “At the exact moment the Field Amplifier accessed the ruined headpiece, a bubble of chronostatic energy formed around the damaged time suit. It sliced through Isambard’s wrist, popped, and the suit, along with our friend’s hand, vanished.”

“It travelled into time,” Babbage snarled. “Of its own accord.”

From amid the complex of jointed metal limbs that hung from the centre of the ceiling like angular jungle lianas, one emerged with a sword clutched in its mechanical digits. Gently, it tapped the blade first against Captain Richard Francis Burton’s right shoulder, then against his left.

The king’s agent stood, now a Knight of the Most Distinguished Order of Saint Michael and Saint George.

Due to the damage done to the monarch’s vocal apparatus during the attack on Buckingham Palace, a white-stockinged royal equerry had spoken the words of the ceremony. Burton felt relieved by this. King Ernest Augustus I was demented at the best of times, and the past three months had been far from the best. Had he been able to express himself, he’d no doubt have ranted endlessly about the violence done to him—for the palace was, in effect, his own body; his limbs were built into every part of it, all controlled from the Crown Room, where his brain floated in a tank of vital fluids. The destruction of the western wing had been the equivalent of having an arm blown off. His Majesty was nettled, to say the least.

Burton took three steps back, bowed, and returned to his seat.

“Did your leg fall asleep?” whispered Monckton Milnes, who was sitting to his left.

“No. Why do you ask?”

“You were limping.”

Burton made a sound of puzzlement. “Was I? By Allah’s beard, I do feel a little strange. My mind was wandering all over the place. I imagined myself to be at Battersea Power Station.”

“Maybe it wasn’t just the leg, then,” his friend suggested, sotto voce. “Perhaps all of you fell asleep. I wouldn’t be at all surprised, despite the occasion. Not after what you’ve been through.”

“I was daydreaming, that’s all. You know I have no patience for these official functions. When can we get out of this asylum?”

“Shhh! The walls have ears.”

Burton mentally kicked himself. “I mean no disrespect to the king, but I was probably thinking of Battersea Power Station because I have to be there by nine o’clock. Babbage is activating Oxford’s suit.”

An abstruse thought intruded. What? Again?

“These ceremonies don’t usually occur so late in the day,” Monckton Milnes observed, “but His Majesty spent all morning with his architects, and the meeting went past its allotted hours. It’s rumoured that he wants the palace rebuilt and made the tallest edifice in the city. I expect he’s eager to get back to his plans and sketches, which is why, believe it or not, formalities are proceeding at such a rapid pace.”

“This is rapid?”

“By comparison to the norm. Be patient, there are only three more to be knighted, then we’ll depart.”

One of the palace footmen gave them an uncompromising glare. They stopped their whispering.

Burton ran his forefinger around his collar. It was too tight. He’d forgotten how uncomfortable a freshly laundered army uniform could be.

Wearily, he endured the pomp and protocols.

Forty minutes later, in the reception hall, the foppishly attired Lord Palmerston approached him and drawled, “My dear Sir Richard, may I be the first to congratulate you.”

“On what, sir?”

“Your title, man! Your title!”

“Ah. Thank you, Prime Minister.”

“I’ve read your report. The Mystery of the Malevolent Mediums. Do you intend to give all your accounts such lurid titles?”

“I felt it appropriate. It was a dramatic affair.”

“I can’t disagree with that. Is it really over?”

“Nietzsche is dead, sir—in our time, in his own, and across all the other versions of history.”

Burton couldn’t shake a curious sensation of unfamiliarity. The environment felt unutterably askew. Even the words that came out of his mouth felt wrong.

“And the future war?” Palmerston asked.

“That rests with you. Now we know it’s coming, you have the opportunity to develop policies that will steer us along another course. There’s no need for the conflict to erupt in 1914. We have fifty-four years in which to prevent it.”