But during his search he had perceived with a slight shock that Helmuth had tightened his defenses even more. Not only was every man in the dome screened against thought, but also each was now wearing full armor. Had he protected the dogs, too? Or killed them? No real matter if he had—any kind of a pet animal would do; or, in a pinch, even a wild rock-lizard! Nevertheless, he shot his perception into the particular barracks he had noted so long before, and found with some relief that the dogs were still there, and that they were still unprotected. It had not occurred, even to Helmuth's cautious mind, that a dog could be a source of mental danger.
With all due precaution against getting even a single grain of the stuff into his own system, Kinnison transferred his thionite into the special container in which it was to be used. Another day sufficed to observe and to memorize the personnel of the gateway observers, their positions, and the sequence in which they took the boards. Then the Lensman, still almost a week ahead of schedule, settled down to await the time when he should make his next move. Nor was this waiting unduly irksome; now that everything was ready he could be as patient as a cat on duty at a mouse hole.
The time came to act. Kinnison took over the mind of the dog, which at once moved over to the bunk in which one particular observer lay asleep. There would be no chance whatever of gaining control of any observer while he was actually on the board, but here in barracks it was almost ridiculously easy. The dog crept along on soundless paws; a long, slim nose reached out and up; sharp teeth closed delicately upon a battery lead; out came the plug. The thought-screen went down, and instantly Kinnison was in charge of the fellow's mind.
And when that observer went on duty his first act was to admit Kimball Kinnison, gray Lensman, to the Grand Base of Boskone! Low and fast Kinnison flew, while the observer so placed his body as to shield from any chance passer-by the all-too-revealing surface of his visiplate. In a few minutes the Lensman reached a portal of the dome itself. Those doors also opened—and closed behind him. He released the mind of the observer and watched briefly. Nothing happened. All was still well!
Then, in every barracks save one, using whatever came to hand in the way of dog or other unshielded animal, Kinnison wrought briefly but effectively. He did not slay by mental force—he did not have enough of that to spare—but the mere turn of an inconspicuous valve would do just as well. Some of those now idle men would probably live to answer Helmuth's call to extra duty, but not too many—nor would those who obeyed that summons live long thereafter.
Down stairway after stairway he dived, down to the compartment in which was housed the great air purifier. Now let them come! Even if they had a spy ray on him, now it would be too late to do them a bit of good. And now, by all the gods of space, that fleet had better be out there, getting ready to blast!
It was. From all over the galaxy that grand fleet had been assembled; every patrol base had been stripped of almost everything mobile that could throw a beam. Every vessel carried either a Lensman or some other highly trusted officer; and each such officer had two detector nullifiers—one upon his person, the other in his locker—either one of which would protect his whole ship from detection.
In long lines, singly and at intervals, those untold thousands of ships had crept between the vessels guarding Grand Base. Nor were the outpost crews to blame. They had been on duty for months, and not even an asteroid had relieved the monotony. Nothing had happened or would. They watched their plates steadily enough—and, if they did nothing more, why should they? And what could they have done? How could they suspect that such a thing as a detector nullifier had been invented?