It had been two hours after the blast that the first drones had gone over what had been Auburn, New York.  He was trying to remember, as exactly as possible, what had been learned from them.  Gamma radiation; a great deal of gamma.  But it didn’t last long.  It had been almost down to a safe level by the time the investigation had been called off, and, two months after there had been no more missiles, and no way of producing more, and no targets to send them against if they’d had them, rather—­he had been back at Auburn on his hopeless quest, and there had been almost no trace of radiation.  Nothing but a wide, shallow crater, almost two hundred feet in diameter and only fifteen at its deepest, already full of water, and a circle of flattened and scattered rubble for a mile and a half all around it.  He was willing to bet anything that that was what they’d find where the chunk of nega-iron had landed, fifty miles away on the pampas.

Well, the first drone ought to be over the target area before long, and at least one of the balloons that had been sent up was reporting its course by radio.  The radios in the others were silent, and the recording counters had probably jammed in all of them.  There’d be something of interest when the first drone came back.  He dragged his mind back to the present, and went to work with Alexis Pitov.

They were at it all night, checking, evaluating, making sure that the masses of data that were coming in were being promptly processed for programming the computers.  At each of the increasingly frequent coffee-breaks, he noticed Pitov looking curiously.  He said nothing, however, until, long after dawn, they stood outside the bunker, waiting for the jeep that would take them back to their bungalow and watching the line of trucks—­Argentine army engineers, locally hired laborers, load after load of prefab-huts and equipment—­going down toward the target-area, where they would be working for the next week.

“Lee, were you serious?” Pitov asked.  “I mean, about this being like the one at Auburn?”

“It was exactly like Auburn; even that blazing light that came rushing down out of the sky.  I wondered about that at the time—­what kind of a missile would produce an effect like that.  Now I know.  We just launched one like it.”

“But that’s impossible!  I told you, between us we know everything that was happening in nuclear physics then.  Nobody in the world knew how to assemble atoms of negamatter and build them into masses.”

“Nobody, and nothing, on this planet built that mass of negamatter.  I doubt if it even came from this Galaxy.  But we didn’t know that, then.  When that negamatter meteor fell, the only thing anybody could think of was that it had been a Soviet missile.  If it had hit around Leningrad or Moscow or Kharkov, who would you have blamed it on?”

THE END.

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