“I must find him,” he muttered, resolutely. “Separation will be fatal.” In vain he called. No answer came back. The Celt, wherever he was, was certainly beyond hearing. In this quandary and a state of mind most indescribable, Frank strove to make his way along in the darkness. He kept on, at intervals shouting for his companion. But ever that same oppressive death-like stillness reigned. Finally Frank was forced to abandon all hope of finding Barney. He next turned his attention to the problem of finding his way out of the place himself. Once he should succeed in doing this and in joining his friends there was no doubt but that he could devise a way to return and make a successful quest for Barney. With this resolution uppermost in his breast he kept on. Suddenly a strange sound burst upon his hearing. It was a distant sound like the mumbling of voices and gave Frank a queer thrill of comprehension. In an instant he realized that he had reached a point in close proximity to those who were searching for him. With this belief Frank cautiously came to a halt. As he did so he heard a slight crunching noise in his rear. Involuntarily he turned about. The next moment he felt a clutch upon his shoulder and then talon fingers closed about his windpipe. Not a word did his assailant speak. Who or what he was Frank could only conjecture. Naturally he believed him to be one of the greasers. But if this was the case, somewhat singularly the fellow made no effort to cry out for his companions. His purpose seemed to overcome Frank without an outcry. But the young inventor had no idea of submitting without a struggle. He grappled with him and a struggle followed which baffles description. Backward and forward they swayed and reeled. Now one held the advantage and now the other. In this manner the struggle continued for some time. In vain Frank tried to throw his adversary. “Who are you?” he finally panted, nigh overcome with exertion. “That’s nothin’ to you,” gritted the other, huskily. “I’m after yer scalp an’ I’m goin’ ter have it.” “Not if I can prevent,” retorted Frank. “Ye can’t help yerself.” “Perhaps not.” “Ye’d better give in at onct. If ye’ll surrender now I’ll spare yer life an’ take ye down to Costello.” “I have no intention of surrendering to you.” “Ye don’t, eh?” “No.” “Curse ye, then I’ll kill ye!” “If you can.” “Wall, I kin.” “Look here!” said Frank, sharply. “I want to know what sort of a chap you are. I can tell by your talk that you are not a greaser.” The fellow laughed. “In course I ain’t,” he replied. “But what of that?” “Well, you must be a miserable wretch to mix up with them.” “That’s nothin’ to you.” “Of course not. Yet I would give one of my own countrymen credit for better sense than that.” “Wall, I don’t ax any odds of you nor nobody else. Let go of my wrist or I’ll stick this knife atwixt yer ribs.” “I have no idea of it.” “Ye haven’t, eh?” “No.” “Wall, I’ll show ye.”