"OK," I said, turning back to the screen. "You're the boss. Do what you like. It's just my reflexes wanting to run. I've got no place to run to. At least with you I've always got the wild hope that maybe you're not completely nuts, and that somehow--" I sat upright, eyes on the screen. "Look at this, Foster," I snapped. A pattern of dots flashed across the screen, faded, flashed again.... "Some kind of IFF," I said. "A recognition signal. I wonder what we're supposed to do now." Foster watched the screen, saying nothing. "I don't like that thing blinking at us," I said. "It makes me feel conspicuous." I looked at the big red button beside the screen. "Maybe if I pushed that...." Without waiting to think it over, I jabbed at it. A yellow light blinked on the control panel. On the screen, the pattern of dots vanished. The red blip separated, a smaller blip moving off at right angles to the main mass. "I'm not sure you should have done that," Foster said. "There _is_ room for doubt," I said in a strained voice. "It looks like I've launched a bomb from the ship overhead." * * * * * The climb back up the tunnel took three hours, and every foot of the way I was listening to a refrain in my head: This may be it; this may be it; this may be it.... I crawled out of the tunnel mouth and lay on my back, breathing hard. Foster groped his way out beside me. "We'll have to get to the highway," I said, untying the ten-foot rope of ripped garments that had linked us during the climb. "There's a telephone at the pub; we'll notify the authorities...." I glanced up. "Hold it," I said. I grabbed Foster's arm and pointed overhead. "What's that?" Foster looked up. A brilliant point of blue light, brighter than a star, grew perceptibly as we watched. "Maybe we won't get to notify anybody after all," I said. "I think that's our bomb--coming home to roost." "That's illogical," Foster said. "The installation would hardly be arranged merely to destroy itself in so complex a manner." "Let's get out of here," I yelled. "It's approaching us very rapidly," Foster said. "The distance we could run in the next few minutes would be trivial by comparison with the killing radius of a modern bomb. We'll be safer sheltered in the cleft than in the open." "We could slide back down the tunnel," I said. "And be buried?" "You're right; I'd rather fry on the surface." We crouched, watching the blue glare directly overhead, growing larger, brighter. I could see Foster's face by its light now. "That's no bomb," Foster said. "It's not falling; it's coming down slowly ... like a--" "Like a slowly falling bomb," I said. "And it's coming right down on top of us. Goodbye, Foster. I can't claim it's been fun knowing you, but it's been different. We'll feel the heat any second now. I hope it's fast."