He had counted one thousand before he stopped to rest; and then the halt was but momentary, more to tighten his belt and shift his shot-gun from one shoulder to the other, than because he was tired. Soon after starting again, he noticed to his satisfaction that he had entered the slight depression which they had observed in the afternoon, and through which it was believed a river ran during the rainy season. Its course there was north to south, where it entered the Marañon. Thus the strength of one link in his theoretical chain had been proven; if the second white rock was directly north from the main river, it undoubtedly stood in the bed of this periodical waterway.
About this time he entered the region of the curious mounds and was able to remain in the little valley, for the waters had washed a way around each, not so deep as the channel, however, proving that a portion of the flow had soaked through the strangely formed hillocks.
At his two-thousandth step the boy noticed that the mounds had increased in size and were closer together. A hundred yards farther they appeared to be merged into one, which was several hundred feet in circumference, and which appeared to be a little table-land, indented by the depression across its surface. At the opposite end from where he had entered the table-land, or rather on the opposite side of the circle, the river-bed swept in an angle to the east.
Perspiration stood in beads on his forehead; his heart beat wildly. Was he right? Was this little table-land, this mound larger than all the others, an elevation at the mouth of the mine? Was the decomposed wood under his feet the remains of trees which had been felled in the greatest number by the Ayulis, because of proximity to the treasure? If these facts were true, then where had the white rock stood? Why, at the point where the river of winter changed its course to the east; that was the most probable point, if the pillar that marked the mine opening bore north from the Marañon, as old Huayno had said.
It took him but a minute to reach this point, and once there he put down his rifle, then commenced to crawl on all fours over the little hillocks with which the big mound was dotted, striking the ground hard blows with his hammer. After having done this for a quarter of an hour or so he stopped, for he was almost out of breath, then when rested he moved to the other side of the depression, at a point a few yards beyond, where it turned east at right angles. There his foot encountered something hard, and throwing himself down, he commenced feverishly to tear aside the vines and creepers that formed a covering. When they were removed he saw a dark brown rock that was covered over with decayed vegetable matter. Scraping this off, the lad made use of his little hammer, and after three or four blows a wonderful thing happened.