are—after sunset!" El Shabur's voice mocked. "Will the knowledge make her turn to you for protection?"
"You fool! Do not meddle with power you cannot control. Until Siwa, then."
They passed out of earshot. Dale watched them return to camp.
"More bite of mosaic, nice lurid color, too. Looks as though Siwa's going to be even more promising than I imagined. Evil old city, enough to make one write another Book of Revelations?"
The sun cast long shadows, stretching grotesquely over pink-stained leagues of sand. Dale was anxious to watch Gunnar when the sun actually did set; he felt that phrase of the young Icelander's had been significant: From sunrise to sunset I will be with her. Rather an odd poetic reference to time! Taken in conjunction with his unexplained disappearance last night, it was specially odd.
Dale ambled slowly in the direction of camp, empty pipe between his teeth. He had stayed a long hour. From his rocky crevice, he had watched Gunnar and the Arab return, seen Gunnar start off again with Merle into the desert. The two were returning now—dark against the reddening sky.
He was curious to see how the young man was going to behave; what explanation, if any, he had given to Merle. He was overwhelmingly anxious to discover just how far she returned the love that burned so stedfastly in Gunnar's eyes. If it was serious—really serious—with her, the whole queer dangerous situation was going to be deadly.
She would go her own way. If her heart was given, it was given, for good or evil. It seemed entirely evil, in his judgment, if she had decided to link her fate with this Icelander.
And El Shabur! How dangerous was this notorious Arab magician? Men of his practises fairly haunted desert cities and oases. Mostly they were harmless, sometimes genuinely gifted in the matter of prophecy. Rarely, they were men of inexplicable and very terrible power; who were dedicated, brain and body, to the cause of evil—evil quite beyond the comprehension of normal people.
Dale's eyes were cold and implacable as he recollected one or two such men he had known: his pleasant face looked unbelievably austere and grim.
One way or another, Merle stood in imminent and pressing danger; from Gunnar, no less than from EI Shabur; from Gunnar, not because he was of himself evil, but because he was a channel through which the Arab could reach her. She was vulnerable in proportion to her love. There were infinite sources of danger ahead. El Shabur had a definite plan regarding her, something that would mature at Siwa. Three days remained to discover the nature of that plan.
Three days! Perhaps not even that. Gunnar's relations with the Arab seemed dangerously explosive; a crisis might work up at any moment. Merle would then be implicated, for she would defend Gunnar with blind partizanship. All the odds were on El Shabur. It was his country; he could queer the expedition easily without any supernatural agency. And, if he were the deadly poisonous creature Dale began to suspect, then the lonely desert made a superb background for murder... he called it murder to himself, unwilling to give a far more terrible name to what he suspected EI Shabur might do.
The lovers, walking slowly, reluctantly back to camp, were completely absorbed in each other.
"If only I'd known you earlier!" The man's sunken eyes looked down on the