For two days Tarzan sought futilely for some clew to the whereabouts of the machine or its occupants. He cached portions of his kills at different points, building cairns of rock to mark their locations. He crossed the first deep gorge and circled far beyond it. Occasionally he stopped and called aloud, listening for some response but only silence rewarded him—a sinister silence that his cries only accentuated.
Late in the evening of the second day he came to the well-remembered gorge in which lay the clean-picked bones of the ancient adventurer, and here, for the first time, Ska, the vulture, picked up his trail. "Not this time, Ska," cried the ape-man in a taunting voice, "for now indeed is Tarzan Tarzan. Before, you stalked the grim skeleton of a Tarmangani and even then you lost. Waste not your time upon Tarzan of the Apes in the full of his strength." But still Ska, the vulture, circled and soared above him, and the ape-man, notwithstanding his boasts, felt a shudder of apprehension. Through his brain ran a persistent and doleful chant to which he involuntarily set two words, repeated over and over again in horrible monotony: "Ska knows! Ska knows!" until, shaking himself in anger, he picked up a rock and hurled it at the grim scavenger.
Lowering himself over the precipitous side of the gorge Tarzan half clambered and half slid to the sandy floor beneath. He had come upon the rift at almost the exact spot at which he had clambered from it weeks before, and there he saw, just as he had left it, just, doubtless, as it had lain for centuries, the mighty skeleton and its mighty armor.
As he stood looking down upon this grim reminder that another man of might had succumbed to the cruel powers of the desert, he was brought to startled attention by the report of a firearm, the sound of which came from the depths of the gorge to the south of him, and reverberated along the steep walls of the narrow rift.
Chapter XV
Mysterious Footprints
As the British plane piloted by Lieutenant Harold Percy Smith-Oldwick rose above the jungle wilderness where Bertha Kircher's life had so often been upon the point of extinction, and sped toward the east, the girl felt a sudden contraction of the muscles of her throat. She tried very hard to swallow something that was not there. It seemed strange to her that she should feel regret in leaving behind her such hideous perils, and yet it was plain to her that such was the fact, for she was also leaving behind something beside the dangers that had menaced her—a unique figure that had entered her life, and for which she felt an unaccountable attraction.
Before her in the pilot's seat sat an English officer and gentleman whom, she knew, loved her, and yet she dared to feel regret in his company at leaving the stamping ground of a wild beast!
Lieutenant Smith-Oldwick, on his part, was in the seventh heaven of elation. He was in possession again of his beloved ship, he was flying swiftly in the direction of his comrades and his duty, and with him was the woman he loved. The fly in the ointment, however, was the accusation Tarzan had made against this woman. He had said that she was a German, and a spy, and from the heights of bliss the English officer was occasionally plunged to the depths of despair in contemplation of the inevitable, were the ape-man's charges to prove true. He found himself torn between sentiments of love and honor. On the one hand he could not surrender the woman he loved to the certain fate that must be meted out to her if she were in truth an enemy spy, while on the other it would be equally impossible for him as an Englishman and an officer to give her aid or protection.