The left turn ahead dumped them into a large, circular room with age-scrubbed frescoes on the walls. It was lined with . . . What were these things? Mechanical devices. Jess tried not to think what they were intended to do, but the spikes, straps, wheels, gears made it all too evident once he focused on the evil things.

It was a torture chamber.

There were no exits.

Jess froze for a moment, thinking, What did I just do? But then he pushed past the others into the center of the room. This was the right place; he knew it was. This chamber was a perfect round replica of the one below their feet, off the sewers. But there was no sign of any metal plate in the floor.

It has to be here, he thought, and pushed aside the thudding headache to concentrate. His eyes fixed on a device in the middle of the room.

“Here! Move this!” he said, and pushed at a particularly large construction that looked like a bed, but with gears and ropes and straps stained with old blood. The stench of it—of the whole room—made his throat close up, but he gritted his teeth and shoved, and Santi and Dario joined him. The machine moved with a long, agonizing screech of metal on metal—because it had been partially blocking the round metal plate set in the center of the floor. The plate was stamped with the screaming face of a monster with snakes for hair—a Gorgon. Ancient work. It had been sealed for a very long time.

Santi removed the Codex from his belt and—to Jess’s surprise—dropped it on the ground before he took a sealed, padded bottle from his pack and said, “Leave your Codices here. Stand back.”

Jess hadn’t thought of it, but Santi was right, of course; the Codex that was so familiar a tool to him could be used against them. It could be tracked, couldn’t it? The Archivist would have Obscurists on it in moments. Morgan had already dropped hers, and so had Wolfe. Jess put his down on the floor, obscurely careful about it, and watched as Glain did the same. It took Khalila and Dario far longer to decide to let go of this last tangible symbol of the Library; Khalila put hers down reverently, as if it might break, and whispered something that sounded to him like a prayer as she pressed her fingertips to the cover.

Then Santi opened the bottle and poured the thick greenish contents over the stack of books. They flared up into a brilliant pyre, and Jess pulled Thomas and Morgan back from the billowing toxic smoke. We’re Burners, Jess thought, stricken. Now we’re Burners.

Through the hanging pall of smoke, as he started to cough, he saw Santi take out two more bottles and pour them over the Gorgon face of the metal plate. This time it didn’t burn; it bubbled as it distorted the Gorgon’s snarl into a slack-mouthed scream, and then hissed and melted it away altogether. The plate was thick, but the chemicals would do the job . . . if they had time.