After the beginning of the Hard Rain, no fire—in the sense of open burning of solid, carbon-rich fuel—had been constructed by humans—by Spacers, anyway—for 1,735 years. It had taken that long to build a habitat large enough to grow trees, with enough atmosphere to handle the oxygen demand of a fire and to absorb the resulting smoke. Ancient digitized Boy Scout manuals had been consulted. It had worked the first time. The four pyro-pioneers responsible—all Dinans—had stood around it, staring into the flames as Ty was doing now, and probably thinking about all that had happened since the last time humans had smelled woodsmoke.