The main building was little more than a roof on stilts straddling the last two hundred feet of the canal. Its trusses were oversized to support a traveling crane with a great hook dangling from a rusty chain, each of whose links was as big as my head. We had seen this structure from the Mynster but never given much thought to it. Teed into its side was a high-roofed hall enclosed by proper walls of brick (below) and corrugated steel (above). Grafted to the side of that, down low, was a shelter module with all sorts of homey touches, such as a fake wood door and a farm-style weathervane, that looked crazy here. We knocked, waited, then pushed our way in. We made lots of noise, just in case this was another one of those places where visitors were put to death. But no one was there.

The module had been designed to serve as a home, but everything in it had been bent to serve the purposes of an office. So for example the shower stall was occupied by a tall cabinet where records were filed. A hole had been sawed into a wall so that little pipes could be routed to a hot-beverage machine. A freestanding urinal had been planted in the bedroom. The only decoration, other than those crazy-looking rustic touches that had shipped with the module, was oddly shaped pieces of metal—parts from machines, I reckoned—some of which had been bent or snapped in traumatic events we could only imagine.

A trail of oily bootprints led us to the back door. This opened straight into the cavernous hall. Both of us hunched our shoulders as we stepped over the threshold. We hesitated just inside. The place was too big to illuminate, so most of the light was natural, shining through translucent panels high up in the walls, each surrounded by a hazy nimbus. The walls and floors were dark with age, congealed smoke, and oil. More hooks and chains dangled from overhead beams. The light washing round these gave them a spindly, eroded look. The floor sprawled away into haze and shadow. Widely spaced around it were crouching masses, some no bigger than a man, others the size of a library. Each was built around a hill of metal: from a distance, smooth and rounded, from up close, rough, which led me to guess that these had been made in the ancient process of excavating molds from sand and pouring in a lake of molten iron. Where it mattered, the rough iron had been cut away to leave planes, holes, and right angles of bare grey metal: stubby feet by which the castings were bolted to the floor, or long V-shaped ways on which other castings could slide, driven by great screws. Huddled beside these things or crouching under them were architectures of wound copper wire, rife with symmetries, and, when they moved, brilliant with azure-tinged lightning. Tendrils of wire and of artfully bent tubing had grown over these machines like ivy exploring a boulder, and my eye followed them to concentrations where I was sometimes surprised to see a human being in a dark coverall. Sometimes these humans were doing something identifiable as work, but more often they were just thinking. The machines emitted noise from time to time, but for the most part it was quiet, pervaded by a low hum that came from warm resonating boxes strewn all round and fed by, or feeding, cables as thick as my ankle.

There were perhaps half a dozen humans in the entire place, but something in their posture made us not dare approach them. One came our way pushing a rusty cart exploding with wild helices of shaved metal.

“Excuse me,” I said, “is Cord here?”

The man turned and extended his hand toward something big and complicated that stood in the middle of the hall. Above it, the rational adrakhonic geometry of the roof-trusses and the infinitely more complex manifolds of swirling mist were magnified and made more than real by the sputtering blue light of electrical fire. If I saw a star of that color through a telescope, I would know it as a blue dwarf and I could guess its temperature: far hotter than our sun, hot enough that much of its energy was radiated as ultraviolet light and X-rays. But, paradoxically, the house-sized complex that was the source of the energy looked orange-red, with only a fringe of the killing radiance leaking out round edges or bouncing from slick places on the floor. As Jesry and I drew closer, we perceived it as a giant cube of red amber with two black forms trapped in it: not insects but humans. The humans shifted position from time to time, their silhouettes rippling and twisting.

We saw that this machine had been robed in a curtain of some red jelly-like matter suspended from an overhead track. The blue light could blast straight up and kill germs in the rafters but it could not range across the floor and blind people. Obviously to me and Jesry, the curtain was red because it had been formulated to let only low-energy light—which our eyes saw as red—pass through it. To high-energy light—which we saw as blue, if we could see it at all—it was as opaque as a steel plate.

We walked around the perimeter, which was about the size of two small shelter modules parked side by side. Through the red jelly-wall it was difficult to resolve fine details of the machine, but it seemed to have a slab-like table, big enough to sleep ten, that eased to and fro like a block of ice on a griddle. Planted in its center was a smaller, circular table that made quick but measured spins and tilts. Suspended above all of this, from a cast-iron bridge, was a mighty construct that moved up and down, and that carried the spark-gap where the light was born.

An arm of tubular steel was thrust forth from the apex of the bridge toward a platform where the two humans stood. Pendant from its end was a box folded together from sheet metal, which looked out of place; it was of a different order of things from the sand-cast iron. Glowing numbers were all over it. It must be full of syntactic processors that measured what the machine was doing, or controlled it. Or both; for a true syntactic processor would have the power to make decisions based on measurements. Of course my thought was to turn away and get out of the room. But Jesry was rapt. “It’s okay, it’s Apert!” he said, and grabbed my arm to turn me back around.

One of the two humans inside said something about the x-axis. Jesry and I looked at each other in astonishment, just to be sure we’d actually heard such a thing. It was like hearing a fry cook speak Middle Orth.

Other fragments came through above the sputtering of the machine: “Cubic spline.” “Evolute.” “Pylanic interpolation.”

We could not keep our eyes off the banks of red numbers on the front of the syntactic processor. They were always changing. One was a clock counting down in hundredths of a second. Others—as we gradually perceived—reflected the position of the table. They were literal transcriptions of the great table’s x and y position, the angles of rotation and tilt of the smaller table in the middle, and the altitude of the sizzling blaster. Sometimes all would freeze except for one—this signaled a simple linear move. Other times they would all change at once, realizing a system of parametric equations.

Jesry and I watched it for half an hour without speaking another word. Mostly I was trying to make sense of how the numbers changed. But also I was thinking of how this place was similar in many respects to the Mynster with its sacred clock in the center, in its well of light.

Then the clock struck, as it were. The countdown stopped at zero and the light went out.

Cord reached up and threw back the curtain. She peeled off a pair of black goggles, and raised one arm to wipe her brow on her sleeve.

The man standing next to her—who I gathered was the customer—was dressed in loose black trousers and a black long-sleeved pullover, with a black skullcap on his head. Jesry and I realized at the same moment what he was. We were dumbstruck.