Harrow flicked through pages with scabby fingers until she had opened the squat book midway, showing three sets of angular diagrams. They appeared to be numerous overlapping squares, with lines coming out at odd angles and a scrawl of notes or numbers bumping up against the lines. The writing was minute and spidery: the squares mazelike and innumerable. Gideon realised after a moment that she was looking at an architectural drawing, and that it was an architectural drawing of Canaan House. It was scribbled thickly with cross marks.
“I’ve divided Canaan House into its three most significant levels, but that’s not quite accurate. The central floor is more of a mezzanine providing access to the top and bottom floors. The terraces are sections in and of themselves, but they’re not important for what I’m identifying here. Each X denotes a door. Current count is seven hundred and seventy-five, and Griddle—only six are locked. The first two hundred doors I identified—”
“You spent this whole time counting doors?”
“This calls for rigor, Nav.”
“Maybe rigor … mortis,” said Gideon, who assumed that puns were funny automatically.
“The first two hundred doors I identified,” Harrow repeated, through gritted teeth, “included the access hatch to the lower area of Canaan House. My method was to start at the bottom and go up as far as I could from a static starting point. There are two lock-points here, at X-22 and X-155. X-155 is the hatch, X-22 is another door. I went to Teacher and asked permission to enter both. He agreed to let me through the hatch if I could provide a safe place for the key, but said that X-22 didn’t belong to him and that he couldn’t in good conscience give permission. All the while he was winking at me so hard that I thought he had suffered a stroke.”
Despite everything, Gideon was starting to get interested. “Okay. Then what?”
“Then in the morning I retrieved the key ring,” said Harrow.
“Hold up, hold up. My key ring, more correctly, but let’s be clear here, you’d counted two hundred doors before the first morning?”
“A head start,” said her necromancer, “is the only advantage one can claim by choice. My other advantage is in workforce. In this case I’m fairly sure that Sextus started a mere two hours after me, and that Eighth House zealot not long after.”
All of this said a lot about the psyche of Harrowhark Nonagesimus, something about Palamedes Sextus, and a little about the mayonnaise uncle, but Gideon was given no time to interrupt. Harrow was continuing, “And I’m not at all sure about the Third. Never mind. Anyway, I’ve spent the majority of my time down the access hatch in the facility. Here.”
Another dry, crackly page was turned. This one was stained with unmentionable fluids and brown patches, which could have been tea and could have been blood. The diagram was much less detailed than the three for the upper levels. In a fat-leaded pencil Harrow had drawn a network of question marks, and some of the rooms were vague sketches rather than the perfectly ruled mazes of the first maps.
Here there were familiar labels: LABORATORY ONE through to LABORATORY TEN. PRESSURE ROOM. PRESERVATION. MORT. WORK ROOM ONE through to WORK ROOM FIVE. And SANITISER, though also: CONTROL ROOM?, CONSOLE? and DUMP ROOM?. It was set out neatly, with corridors all the same width and doors in expected places. It reminded Gideon of some of the oldest parts of the Ninth House, the bits secluded deep below the more modern twisty little hallways and crooked walls with squints.
“It’s very old,” Harrow said, quietly, more to herself than to Gideon. “Considerably older than the rest of Canaan House. It’s pre-Resurrection—or made to look pre-Resurrection, which is just as curious. I know Sextus is obsessed with dating the structure, but as usual, he’s getting caught up in the details. What’s important is the function.”
“So what was it for?”
Harrow said, “If I knew that, I’d be a Lyctor already.”
“Do you know who used it?”
“That’s a much better question, Nav.”
“And why,” said Gideon, “were you down there with your ass kicked to hell, hiding in a bone?”
The Reverend Daughter sighed heavily, then had a fit of coughing, which served her right. “Whoever left the facility also left the majority of their work behind and intact. No theorems or tomes, unless they’ve been removed—and I doubt Teacher removed them—but, as I’ve discovered, it’s possible to trigger … tests. Theorem models that they would have used. Most of the chambers down there were used to prepare for something, and they were left in a state where anyone who comes across it can re-enact the setup. Someone left—challenges—down there for any necromancer talented enough to understand what they were doing.”