Beyond it a wire cage dangled beneath Parliament’s obsidian skin, with one open side flush with the doorway. It was suspended above and on either side by chains that swung gently, rattled and disappeared into an eddying darkness that loomed off without remission in all directions that the clerk could see. The clerk lugged the crate up into the passageway and slid it along into the cage, which pitched a little under the weight.

He released a hatch which closed sharply, enclosing the crate and its contents with woven wire on all sides. Then he closed the sliding door, reached into his pocket and pulled out the thick programme cards he carried, each clearly marked: Militia; Intelligence; Exchequer, and so on. He slid the relevant card into the slot beside the door.

There would be a whirr. Tiny, sensitive pistons reacted to the pressure. Powered by steam driven up from the vast basement boilers, gentle little cogs rotated the length of the card. Where their spring-loaded teeth found sections cut from the thick board, they slotted neatly inside for a moment, and a minuscule switch was thrown further along the mechanism. When the wheels had completed their brief passage, the combination of on-off switches translated into binary instructions that raced in flows of steam and current along tubes and cables to hidden analytical engines.

The cage jerked free of its moorings and began a swift, swinging passage beneath the skin of Parliament. It would travel the hidden tunnels up or down or sideways or diagonally, changing direction, transferring jerkily to new chains, for five seconds, thirty seconds, two minutes or more, until it arrived, slamming into a bell to announce itself. Another sliding door opened before it, and the crate was pulled out into its destination. Far away, a new cage swung into place outside the clerk’s room.

The Acquisitions clerk worked quickly. He had logged and sent on almost all the assorted oddities before him within fifteen minutes. That was when he saw one of the few remaining parcels shaking oddly. He stopped scribbling and prodded it.

The stamps that adorned it declared it newly arrived from some merchant ship, the name obscured. Neatly printed across the front of the package was its destination: Dr. M. Barbile, Research and Development. The clerk heard a scraping. He hesitated a moment, then gingerly untied the string that bound it and peered inside.

Inside, in a nest of paper shavings that they nudged fitfully, were a mass of fat grubs bigger than his thumb.

The clerk recoiled and his eyes widened behind his glasses. The grubs were astonishingly coloured, beautiful dark reds and greens with the iridescence of peacock feathers. They floundered and wriggled to keep themselves on their stubby, sticky legs. Thick antennae poked from their heads, above a tiny mouthpiece. The hind part of their body was covered in multicoloured hairs that bristled and seemed coated in thin glue.

The fat little creatures undulated blindly.

The clerk saw, too late, a tattered invoice attached to the back of the box, half-destroyed in transit. Any invoiced package he was supposed to record as whatever was listed, and send on without opening.

Shit, he thought nervously. He unfolded the torn halves of the invoice. It was still quite legible.

SM caterpillars x 5. That was all.

The clerk sat back and pondered for a moment, watching the hairy little creatures crawl over each other and the paper they sat in.

Caterpillars? he thought, and grinned fleetingly, anxiously. He kept glancing at the corridor before him.

Rare caterpillars…Some foreign breed, he thought.

He remembered the whispers in the pub, the winks and nods. He’d heard a chap at his local offering money for such creatures…The rarer the better, he’d said…

The clerk’s face wrinkled suddenly in avarice and fear. His hand hovered over the box, darting back and forth inconclusively. He got up and stalked over to his room’s entrance. He listened. There was no sound from the burnished corridor.

The clerk returned to his desk, calculating risk and benefit frantically. He looked closely at the invoice. It was stamped with an illegible crest, but the actual information was handwritten. He fumbled in his desk drawer without giving himself time to think, his eyes darting constantly back to the deserted passage outside his doorway, and brought out a paper-knife and a quill. He scratched with the sharp knife at the straight line on the top and the end of the curl on the bottom of the 5 on the invoice, gently, gently, shaving them away. He blew away paper- and ink-dust, smoothed the roughened paper carefully with the feathered end of his quill. Then he turned it around and dipped the fine point in his inkwell. Meticulously, he straightened the curling base of the digit, converting it into crossing lines.

Eventually, it was done. He straightened up and squinted critically down at his handiwork. It looked like a 4.

That’s the hard bit, he thought.

He felt about him for some container, turned his pockets inside out, scratched his head and thought. His face lit, and he pulled out his glasses case. He opened it and filled it with shredded paper. Then, his face wrinkling with anxious disgust, he pulled the edge of his sleeve down over his hand and reached into the box. He felt the soft edges of one of the big caterpillars between his fingers. As gently and quickly as he could, he plucked it squirming from its fellows and dropped it into his glasses case. Quickly, he closed the case around the frantically twitching little creature and fastened it.

He buried his glasses case at the bottom of his briefcase, behind mint-sweets and papers and pens and notebooks.

The clerk retied the string on the box, then sat back quickly and waited. His heart was very loud, he realized. He was sweating a little. He breathed deeply and squeezed his eyes closed.

Relax, now, he thought soothingly to himself. That’s your bit of excitement over.

Two or three minutes passed, and no one came. The clerk was still alone. His bizarre embezzlement had gone unnoticed. He breathed easier.

Eventually he looked again at his forged invoice. It was, he realized, very good. He opened the ledger and entered, in the section marked R amp;D, the date and the information: 27th Chet, Anno Urbis 1779: From merchant ship X. SM caterpillars: 4.

The last number seemed to glare at him as if it was written in red.

He typed the same information onto his day-sheet before picking up the resealed box and carrying it over to the wall. He opened the sliding doors and leaned into the little metal threshold, pushed the box of grubs into the waiting cage. Gusts of stale, dry air billowed onto his face from the dark cavity between the hide and guts of Parliament.

The clerk pulled the cage shut and closed the door before it. He fumbled for his programme cards, eventually pulling the one marked R amp;D from the little pack with fingers that still trembled, just a little. He slotted it into the information engine.

There was a juddering hiss and a ratcheting sound as the instructions fed along pistons and hammers and flywheels and the cage was pulled vertiginously up, away from the clerk’s office, beyond Parliament’s foothills, into the craggy peaks.

The box of caterpillars swung as it was tugged through the darkness. Oblivious to their journey, the grubs circumscribed their little prison with peristaltic motion.

Quiet engines transferred the cage from hook to hook, changing its direction and dropping it onto rusted conveyor-belts, retrieving it in another part of Parliament’s bowels. The box spiralled invisibly around the building, rising gradually and inexorably towards the high-security East Wing, passing through mechanized veins to those organic turrets and protuberances.