The next chamber was three hundred yards across. Violet mist hid the bottom of a deep trench.
An eighty-foot bridge crossed it. Eighty dragon vertebrae formed the deck, laced together with steel cable. Copper coils hung beneath the bones, and four five-inch steel cables anchored the span to the rock.
A yellow sign marked the entrance.
[CHAMBER 02: STRUCTURAL TENSION AND DYNAMIC LOAD TEST GANTRY]
[CALIBRATE EACH STAGE BEFORE ADVANCING]
Austin crouched beside the control box. “The field rises toward the far side. My own field is fourteen times normal, so the controller should read an overload and push upward.”
Xiaoyao looked from the bridge to the sign. “Should we test that before all three of us step on?”
“First stage is rated above us.” Austin stepped onto the first vertebra. “See? Light already.”
He took another stride. The copper coil flashed red.
Instead of lifting him, the field slammed downward.
Austin dropped to one knee. The bone beneath him tilted, and the bridge swung over the mist. Xiaoyao grabbed the entrance cable with one hand and Austin’s tool belt with the other. Pug planted all four paws behind the boy and leaned back.
The wrench slipped from Austin’s shoulder. Xiaoyao caught its strap before it vanished into the trench.
“Wrong assumption,” Austin grunted. “It adds load to match the target. Doesn’t cancel mine.”
“Can you step back?”
“Not without dragging you both forward.”
Xiaoyao forced himself to look at the control box instead of the drop. A needle had passed its green mark. Beside it sat a handwheel labeled LOCAL LOAD TRIM.
“Master, there is a manual trim. What does it do?”
“Sets the stage target. Turn it toward zero.”
Xiaoyao hooked one leg around the support post. Keeping his weight low, he reached for the wheel. It would not move.
“Pug, hold the cable steady. Not tighter. Steady.”
Pug braced his shoulders. The swing slowed enough for Xiaoyao to pull a small spanner from Austin’s belt and free the wheel’s locking collar. He turned it half a rotation.
The crushing force eased. Austin crawled back onto solid ground, and all three collapsed beside the control box.
For a moment, nobody spoke.
Austin accepted his wrench. “That was my mistake. I assumed the controller worked against load. It works toward a set load. Good call on the trim.”
Xiaoyao let out a breath. “You did say not to trust an answer because it was loud.”
“I did. Keep doing that.”
They inspected the bridge together. Each stage had a manual trim wheel and a gauge. The controller could hold a safe downward field, but someone had to set it before the others crossed. No single person could watch the gauge, move across the deck, and keep the bridge steady at the same time.
Austin tied a safety line around his waist and passed the other end to Xiaoyao. “New plan. I carry the load. You call the readings. Pug keeps the safety line from going slack.”
Xiaoyao wiped dust from the first gauge. “Set at one and a half. Green mark. Move when I say.”
They crossed in eight stages. Xiaoyao remained at each control station until Austin reached the next bone, then followed while Austin held the trim. Pug stayed between them, his broad body keeping the safety line off the sharp vertebrae.
At the fourth stage, the field began to climb before Austin gave the signal.
“Stop,” Xiaoyao said. “Needle is hunting. The contact is dirty.”
Austin braced while Xiaoyao cleaned the contact with a folded strip of emery cloth. The needle settled. Only then did they move.
At the sixth, a suspension cable began to sing. Pug’s outer heads turned toward it.
“He hears something,” Xiaoyao said.
Austin touched the deck. “Vibration. Ease the field by two points.”
The note faded.
They reached the far side after twenty-three careful minutes. Austin’s shirt was damp with sweat. Xiaoyao’s fingers ached from the trim wheels. Pug shook himself, offended by the whole arrangement.
The terminal chimed.
Austin entered the actual time on his clipboard without complaint. “That’s how a load test is supposed to work.”
Xiaoyao looked back at the bridge. “And if the first guess fails?”
“Stop, get safe, and change the plan.” Austin picked up his wrench. “A wrong guess is information. Pretending it was right is how people get hurt.”
Heat rolled beneath the door to Sector 3. This time, Austin read the warning sign twice before touching the handle.