"When I spoke to him he merely stared blankly, although I was certain that he understood my words. His lips moved to answer but no words formed in his throat.
"I shook him by the arm.
"'I think,' I said to him, pointing to the opening from which Abaris had come into the chamber and into which he had doubtless vanished, 'that we had better find Allie Lane and her father if we hope to get out of here alive. You know that she's here and alive, don't you, Sands?'
"To me it appeared that he made an attempt to speak when he heard Allie's name mentioned, but he merely stared dumbly. At any rate I believed he understood what I had said.
"'If we can get to Allie and her father without these critters knowing it,' I whispered into his ear, 'she might be able to point a way out of here. If we can get out I'll strike toward Stovepipe Wells and send a telegram to Los Angeles asking for help. I'm afraid we'll need a couple of bombing planes from San Pedro to get us out of this mess!'
"I grabbed him by the arm and hustled him toward the circular shaft leading from the chamber. He came readily enough but when I loosened the pressure on his arm he stood there, stock still. He seemed to have no will power whatever and his legs moved only because I hustled him along.
"As we entered the only open shaft leading out of the chamber, a high-pitched musical note became audible. I wondered if our movements had sounded some mysterious warning. As we continued on into the luminous tunnel that glittered with deposits of priceless gems, the musical note rose higher and higher so that it seemed to tax the sense of hearing to its uttermost. Questioningly I turned to Sands. One of his trembling hands was chafing his temples with thumb and forefinger. The sound gradually became a wail like the metallic scream we had heard before entering the cave that led down to the chamber.
"Suddenly I became aware that Sands had broken the influence that had held him! With a frenzied scream he leaped aside and away from me. I gazed in wonder at the man as he crouched like a beast at bay. I expected him momentarily to spring at my throat. But he finally recognized me and became controlled when I assured him the Jovians were not in sight. His first questions were of Allie Lane. Had he really seen her, he wanted to know, or had he been suffering from a brain fever? Was she really alive—as beautiful as ever? I assured him that she was.
"'Lord!' he gasped, shuddering. 'That noise would drive a man insane!'
"'Yes,' I whispered softly, 'But you ought to thank it for bringing you to your senses!'