They could not be guards at all, Kinnison concluded, but must be simply outposts, set far outside the solar system of the planet they guarded; not to ward off one-man speedsters, but to warn Helmuth of the possible approach of a force large enough to threaten the Grand Base of Boskonia.
Closer and closer Kinnison flashed, discovering that the central object was indeed a base, startling in its immensity and completely and intensively fortified; and that the outposts were huge, floating fortresses, practically stationary in space relative to the sun of the solar system they surrounded. The Lensman aimed at the center of the imaginary square formed by four of the outposts and drove in as close to the planet as he dared. Then, going inert, he set his speedster into an orbit—he did not care particularly about its shape, provided that it was not too narrow an ellipse—and cut off all his power. He was now safe from detection. Leaning back in his seat and closing his eyes, he hurled his sense of perception into and through the massed fortifications of Grand Base.
For a long time he did not find a single living creature. He traversed hundreds of miles, perceiving only automatic machinery, bank after towering, mile-square bank of accumulators, and remote-controlled projectors and other weapons and apparatus. Finally, however, he came to Helmuth's dome; and in that dome he received another severe shock. The personnel in that dome were to be numbered by the hundreds, but he could not make mental contact with any one of them. He could not touch their minds at all; he was stopped cold. Every member of Helmuth's band was protected by a thought-screen as effective as the Lensman's own!
Around and around the planet the speedster circled, while Kinnison struggled with this new and entirely unexpected setback. This looked as though Helmuth knew what was coming. Helmuth was nobody's fool, Kinnison knew; but how could he possibly have suspected that a mental attack was in the book? Perhaps he was just playing safe. If so, the Lensman's chance would come. Men would be careless; batteries weakened and would have to be changed.
But this hope was also vain, as continued watching revealed that each battery was listed, checked, and timed. Nor was any screen released, even for an instant, when its battery was changed; the fresh power source being slipped into service before the weakening one was disconnected.
"Well, that proves that Helmuth knows," Kinnison cogitated, after watching vainly several such changes. "He's a wise old bird. The guy really has jets. I still don't see what I did that could have put him wise to what was going on."
Day after day the Lensman studied every detail of construction, operation, and routine of that base, and finally an idea began to dawn. He shot his attention toward a barracks he had inspected frequently of late, but stopped, irresolute.
"Uh-uh, Kim, maybe better not," he advised himself. "Helmuth's mighty quick on the trigger, to figure out that Boyssian thing so fast——"
His projected thought was sheared off without warning, thus settling the question definitely. Helmuth's big apparatus was at work; the whole planet was screened against thought.