Huo Lie lowered his head and looked over the water turbine blueprint again. "I can build this."
Xiao Yun nodded. "Good, but there's no rush. Build a few small ones first and test them. Once they're running properly, we can consider scaling up."
Huo Lie said nothing more. He simply pulled the blueprint closer and examined several of the marked dimensions.
The sunlight on the desk slowly shifted an inch along the edge of the paper.
Outside the window, the wind rounded a corner along the foot of the wall and lifted the corner of the blueprint that the paperweight did not hold down. Huo Lie promptly reached out and pressed it flat.
His fingertips rested against the paper, as though measuring the spaces between the dense annotations in that corner, or waiting for Xiao Yun to finish speaking. A moment later, he gathered the blueprint in front of him and did not let go again.
Light filtered through the window lattice onto the blueprint spread across the desk, traced a circuit along its fine lines, then slowly slid toward the desk's edge and fell on the spreading water marks on the gray brick floor, which the wind dried away.
Xiao Yun did not disturb the two of them. He picked up some of the documents about the territory piled on the desk.
Only after a long while did Huo Lie raise his head and speak slowly. "I understand all of this now, but how do we create the vacuum inside that tungsten-filament light bulb?"
Xiao Yun considered it for a moment. This was fairly simple; all they needed was a device to pump out the air.
As soon as Xiao Yun described the air pump, Huo Lie understood. Its structure was simply the reverse of the bellows used for