"I think it will be better if we remain together," said Edith. "If you and Mr. Verslun did discover an opening it would be exceedingly difficult to find your way back here, and if you got out of this place you might not be able to reach the opening through which we were lowered. Perhaps the way to it is known only to Leith."

Edith's argument was sound. Our finding them in that black cavern was purely an accident, and it was hardly probable that Holman and myself would be able to find our way back to the spot if we went off on a tour of investigation. Personally I had no desire to leave the girls. Leith's deviltry had so impressed me that I considered him capable of anything, and if he thought we were out of the way, I had no doubt that he would take immediate steps to break down the courage of the Professor and his daughters by means that were familiar to him. I could well understand that Edith Herndon's love for her father would compel her to sacrifice herself if she saw the aged Professor in front of the great stone centipede, and that might happen at any moment now that Leith considered that he had disposed of all active opposition.

For hours we debated the matter, and finally the Professor was won over. He agreed to move forward on an inspection tour of the vast subterranean place the moment the next supply of food came from above, and we waited anxiously. During the wait Holman and I made short trips into the darkness, but we were careful that we did not get out of the hearing of the two girls, who called at intervals so that we would be able to find our way back. The place was awe-inspiring. Its size could only be guessed at. Stones that were flung in a certain direction where the floor sloped gradually downward could be heard rolling for many minutes after they left our hands.

We guessed that it was early morning when we heard from Leith. A blazing torch illuminated a round hole about seventy feet above our heads, and Holman and I immediately remained quiet so that the big scoundrel would be in ignorance of the reunion. There was no possibility of the torchlight making our presence known. It would take a score of torches to enable him to see us.

Leith thrust his head over the edge of the hole while Soma held the torch, and, with a coarse laugh, the ruffian inquired if his victims had changed their minds.

"No, we have not," replied the Professor, his thin, quavering voice sounding strangely weak after the deep-throated bellow of the bully on top.

"Well, you'll change it soon," cried Leith. "I'll leave you down there for another day or two, and then I'll get you up to do some stunts. Mind you, I mean a proper marriage with Miss Edith, Professor! The Waif will run us up to the German missionary station while you take charge here for your affectionate son-in-law."

I opened my mouth to fling an answer at the taunting scoundrel, but Holman surmised my intention and begged me to hold my tongue.

"They'll get no food if you cry out!" he whispered. "Don't speak to him, man!"

The Professor made no answer to the offensive remark, and after a few minutes' silence Leith drew back, and Soma started to lower a bundle of food into the dark prison.