Many other stories the veteran told, but what most affected Ab was his account of the vale of fire. He hoped to see it sometime. CHAPTER XIII. AB'S GREAT DISCOVERY. It may be that never in what was destined to be a life of many changes was Ab happier than in this period of his lusty boyhood and early manhood, when there was so much that was new, when he was full of hope and confidence and of ambition regarding what a mighty hunter and great man he would become in time. As the years passed he was not less indefatigable in his experiments, and the day came when a marvelous success followed one of them, although, like most inventions, it was suggested in the most trivial and accidental manner. It chanced one afternoon that Ab, a young man of twenty now, had returned early from the wood and was lying lazily upon the sward near the cave's entrance, while, not far away, Bark and the still chubby Beechleaf were rolling about. The boy was teasing the girl at times and then doing something to amuse or awe her. He had found a stiff length of twig and was engaged in idly bending the ends together and then letting them fly apart with a snap, meanwhile advancing toward and threatening with the impact the half-alarmed but wholly delighted Beechleaf. Tired of this, at last, Bark, with no particular intent, drew forth from the pouch in his skin cloak a string of sinew, and drawing the ends of the strong twig somewhat nearly together, attached the cord to each, thus producing accidentally a petty bow of most rotund proportions. He found that the string twanged joyously, and, to the delight of Beechleaf, kept twanging it for such time as his boyish temperament would allow a single occupation. Then he picked from the ground a long, slender pencil of white wood, a sliver, perhaps, from the making of a spear shaft, and began strumming with it upon the taut sinew string. This made a twang of a new sort, and again the boy and girl were interested temporarily. But, at last, even this variation of amusement with the new toy became monotonous, and Bark ceased strumming and began a series of boyish experiments with his plaything. He put one end of the stick against the string and pushed it back until the other end would press against the inside of the twig, and the result would be a taut, new figure in wood and string which would keep its form even when laid upon the ground. Bark made and unmade the thing a time or two, and then came great disaster. He had drawn the little stick, so held in the way we now call arrowwise, back nearly to the point where its head would come inside the bent twig and there fix itself, when the slight thing escaped his hands and flew away.