His eyebrows went up; I hadn’t given a lot of detail about the purpose of the meeting, except to say that I wanted to talk about megastructures. He accepted the files as I offered them and converted them to paper idioms, then started flipping through the stack. He muttered a few sentences, then his eyes grew rounder and wider and he went silent. Several times he flipped back to earlier pages. Finally he converted the idiom to a 3D image. Hanging between us was a four-segment-long stretch of Heaven’s River.