The runner to the cave of One-Ear was a hunter living some miles to the north, upon a ledge of a broad forest-covered plateau terminating on the west in a slope which ended in a precipice with more than a hundred feet of sheer descent to the valley below. On rare occasions a herd of mammoths invaded the forest and worked itself toward the apex of the plateau, and then word went all over the region, for it was an event in the history of the cave men. If but a sufficient force could be suddenly assembled, food in abundance for all was almost certainly assured. The prize was something stupendous, but prompt action was required, and there might be tragedies. As bees hum and gather when their hive is disturbed, so did the Shell People when Ab burst in upon them and delivered his message. There was rushing about and a gathering of weapons and a sorting out of men who should go upon the expedition. But little time was wasted. Within half an hour Ab was straining back again up the river toward his own abode, while behind him trailed half a hundred of the Shell People, armed in a way effective enough, but which, in the estimation of the cave men, was preposterous. The spears of the Shell People had shafts of different wood and heads of different material from those of the cave men, and they used their weapons in a different manner. Accustomed to the spearing of fish or of an occasional water beast, like a small hippopotamus, which still existed in the rivers of the peninsula, they always threw their spears--though the cave people were experts with this as well--and, as a last resource in close conflict, they used no stone ax or mace, but simply ran away, to throw again from a distance, or to fly again, as conditions made advisable. But they were brave in a way--it was necessary that all who would live must have a certain animal bravery in those days--and their numbers made them essential in the rare hunting of the mammoth. When the company reached the home of Ab they found already assembled there a score of the hill men, and, as the word had gone out in every direction, it was found, when the rendezvous was reached, which was the cave of Hilltop, the man living near the crest of the plateau, and the one who had made the first run down the river, that there were more than a hundred, counting all together, to advance against the herd and, if possible, drive the great beasts toward the precipice. Among this hundred there was none more delighted than Ab and Oak, for, of course, these two had found each other in the group, and were almost like a brace of dogs whining for the danger and the hunt.