He probed; carefully but thoroughly. When he had talked to the Arpalone he had read him easily enough, but here there was nothing whatever to read. The creature simply was not thinking at all. But that didn't make sense! Garlock tuned, first down, then up; and finally, at the very top of his range, he found something, but he did not at first know what it was. It seemed to be a mass-detector ... no, two of them, paired and balanced. Oh, that was it! One tuned to humanity, one to the other guardians--balanced across a sort of bridge--_that_ was how they kept the ratio so constant! But why? There seemed to be some wide-range receptors there, too, but nothing seemed to be coming in.... While he was still studying and still baffled, some kind of stimulus, which was so high and so faint and so alien that he could neither identify nor interpret it, touched the Arpalone's far-flung receptors. Instantly the creature jumped, his powerful, widely-bowed legs sending him high above the heads of the crowd and, it seemed to Garlock, directly toward him. Simultaneously there was an insistent, low-pitched, whistling scream, somewhat like the noise made by an airplane in a no-power dive; and Garlock saw, out of the corner of one eye, a yellowish something flashing downward through the air. At the same moment the woman immediately in front of Garlock stifled a scream and jumped backward, bumping into him and almost knocking him down. He staggered, caught his balance, and automatically put his arm around his assailant, to keep her from falling to the sidewalk. * * * In the meantime the guardian, having landed very close to the spot the woman had occupied a moment before, leaped again; this time vertically upward. The thing, whatever it was, was now braking frantically with wings, tail, and body; trying madly to get away. Too late. There was a bone-crushing impact as the two bodies came together in mid-air; a jarring thud as the two creatures, inextricably intertwined, struck the pavement as one. The thing varied in color, Garlock now saw, shading from bright orange at the head to pale yellow at the tail. It had a savagely-tearing curved beak; tremendously powerful wings; its short, thick legs ended in hawk-like talons. The guardian's bowed legs had already immobilized the yellow wings by clamping them solidly against the yellow body. His two lower arms were holding the frightful talons out of action. His third hand gripped the orange throat, his fourth was exerting tremendous force against the jointure of neck and body. The neck, originally short, was beginning to stretch.