“Just as you say, chief. Here’s my report in full. Some of the stuff will jar you to the teeth; particularly Fairchild and the fact that every blow-up that has ever happened has been deliberate, not accidental.” “Huh? _Deliberate!_ Have you blown your stack completely, Storm?” “Uh-uh; but the proof is too long and involved to go into offhand. You’ll have to get it from the tapes and it’ll take you at least a week to check my math. Besides, you told us to flit. So come on, Joan—clear ether, Phil!” The Blaster and his new assistant left the laboratory; and in the copter, en route to the field, Cloud wondered momentarily what it was about the Lensman’s explanation that had not rung quite true. The first sight of his new vessel’s control room, however, banished the unformed thought from his mind before it had taken any real root. * * * * * The transformed scout cruiser _Vortex Blaster II_ hung poised and motionless over the badlands. The optical systems and beam-antennae and receptors of dozens of instruments, many of which were only months old, were focused sharply upon the loose atomic vortex a scant two miles distant. A few of these instruments reported only to a small and comparatively simple integrator which, after classifying and combining the incoming signals, put out as end-product the thin, black, violently-fluctuating line which was the sigma curve. Some others reported only to a massive mechanism, too heavy for any smaller vessel to carry, upon whose electronic complexities there is no need to dwell. Most of the information-gathering instruments, however, reported to both integrator and computer. Not strapped down into a shock-absorber, but sitting easily in an ordinary pilot’s bucket, quietly but supremely intent, “Storm” Cloud concentrated upon his sigma curve; practically oblivious to everything else. Without knowing how he did it he was solving continuously the simultaneous differential equations of the calculus of warped surfaces; extrapolating the sigma curve to an ever-moving instant of time three and nine-tenths seconds—the flight-time of the bombs plus his own reaction time—ahead of the frantic pen-point of the chart. In his flitter, where he had required a nine- or ten-second prediction, he had always seized the first acceptable match that appeared. Now, however, needing only to extrapolate to less than four seconds, his technique was entirely different. He was now matching, from instant to instant, the predicted value of the curve against one or another of the twelve bombs lying in the firing chambers of heavy guns whose muzzles ringed the cruiser’s needle-sharp nose.