"They could never have gotten out there and back so fast!" he shouted. "We'll be passing through a section of the Colony in about two more minutes. It's closer to the hospital, so it's just possible they've picked up a few victims at the fringe of the blast area who didn't have our luck." "The fallout area must be pretty wide!" I shouted back. "Wherever the explosion took place--" He cut me off again. "No fallout--or very little. What there is is gone within four or five minutes. Safe to go in after that, for the residue wouldn't mutate a fruitfly. Colonists don't know that ... closely guarded Endicott trade secret. Reason we let the Colonists store them. A fuel cylinder can be converted into a nuclear bomb, all right, but it will be the cleanest midget bomb ever built. Take fifteen or twenty of them to blow up even a third of the Colony. But that doesn't mean that one couldn't blow up the spaceport, or seriously injure hundreds of people throughout the fringe area. The ground tremor alone could do that. I told you what it did to this tractor. Has the force of a small earthquake, except that the tremors are three times as erratic. They can just shake you up a little, or break every bone in your body. Depends on where you happen to be standing. It follows a zigzagging pattern, so it can pass right by you." All that didn't come in one shout, but I'm recording it that way because I didn't interrupt him, and though he must have stopped once or twice to take a deep breath, and keep a sharp lookout for another ambulance I wasn't aware of any break in what he was saying. He was trying his best to make it crystal clear, if only to calm me down a little. Some of it was reassuring, but not what he'd said about the spaceport. A clean bomb with little or no fallout can leave you just as dead if you're unfortunate enough to be blown up by it. You see things sometimes you can't bring yourself to talk about, even to close friends when the horror has receded a little and you know it can't come back in a physical way to torment you. So I'm going to draw the veil over most of what we saw when we passed through about five square miles of the Colony, before the clear-away broadened out to twice its previous width and we headed out across the desert toward the spaceport. We couldn't be sure, even then, just where the explosion had taken place, because it was only the fringe area we passed through. It hadn't been laid waste by the blast and there were only five or six demolished buildings. If the big square which stretched between the Endicott plant and the aerators had been a built-up section instead of a square the property damage might have been just as great and would not have seemed ruinous.