Burl's followers were already in panic-stricken flight. He could hear them crashing through obstacles as they ran glassy-eyed from the horror they only imagined, but which Burl could not but encounter. Burl shivered, his body poised for equally frenzied but quite hopeless flight. But his first step was blocked. There was a boulder behind him, standing on end, reaching up to his knee. He could not take the first step without dodging it.
It was not the Burl of the terror-filled childhood who acted then. It was the throw-back, the atavism to a bolder ancestry. While the Burl who was a product of his environment was able to know only the stunned sensations of purest panic, the other Burl acted on a sounder basis of desperation. The emerging normal human seized the upright boulder. He staggered to the rock-face with it. He dumped it down the line of the descending cable.
Humans do have ancestral behavior-patterns built into their nervous systems. A frightened small child does not flee; it swarms up the nearest adult to be carried away from danger. At ten a child does not climb but runs. And there is an age when it is normal for a man to stand at bay. This last instinct can be conditioned away. In Burl's fellows and his immediate forbears it had been. But things had happened to Burl to break that conditioning.
He flung the pointed boulder down. For the fraction of a second he heard only the bubbling, gnashing sounds the spider made as it climbed toward him. Then there was a quite indescribable cushioned impact. After that, there were seconds in which Burl heard nothing whatever--and then a noise which could not be described either, but was the impact of the spider's body on the ground a hundred feet below, together with the pointed boulder it had fought insanely during all its fall. And the boulder was on top. The noise was sickening.
Burl found himself shaking all over. His every muscle was tense and strained. But the spider did not crawl over the edge of the precipice and something had hit far below.
The nest still dangled at the end of the single cable, festooned with its gruesome trophies. But Burl saw the spider. It was, of course, characteristically tenacious of life. Its legs writhed and kicked, but the body was crushed and mangled.