The spot at which they were camped was the sheer, or cliff side of the mesa. At the other side they knew, from Coyote Pete's description, were numerous openings and a zig-zag pathway leading up to the very summit. It was on this summit, which according to the most accurate information obtainable had once been used for the sacrificial rites of sun worship, that the professor expected to find the relics for which he was searching. For an hour or two the lads discussed the dead-and-gone mesa dwellers, with an occasional word from the professor, who was deeply read on the subject. This was all so much Greek to Pete, who solemnly smoked away, every now and then putting in a word or two, but for the most part lying in silence, looking out beyond the black shadow of the mesa across the moonlit desert toward the rocky hills to the south. Suddenly, the lanky cowboy leaped to his feet with a yell that punctured the silence like a pistol-shot. In two flying leaps, he had bounded clear over the professor's head, and was in among the tents, searching for his pistol. Before one of the amazed group about the fire could collect his senses at the sudden galvanizing of Coyote Pete, he was back among them again. "Wow!" he yelled into the night, "come on, there, you, whoever you are! Come on, I say! I'll give you a fight! Yep, big as you are, I ain't skeered of you." "Pete! Pete! Whatever is the matter?" gasped Jack, who, with the others, was by this time on his feet. "Matter?" howled Pete. "Matter enough. I do begin to think this place shore is haunted, or suthin'. As I lay there, I felt suthin' tiptoeing about behind me, and when I whipped suddenly round ter see if one of the critters hadn't broken loose, what did I see but a great, big, enormous thing, as big as a house, looking down at me. Afore I could say a word, it was gone." "Gone!" echoed the others. "What was it?" "Wish you'd tell me," sputtered the cow-puncher, looking about him, and still gripping his gun, "I never saw the like in all my born days." "Well, what did it look like?" "Hard to tell you," rejoined Pete. "It was as big as that." He pointed right up at the moon. "As tall as the moon? Oh, come, Pete, you had dropped off and were dreaming," laughed Ralph. "Who said it was as tall as the moon?" demanded the excited cow-puncher angrily. "I only meant to convey to your benighted senses some idee uv what it luked like." "Well, how high was it?" asked Jack, in whose tones was a curious note of interest, for a reason we can guess. "About twenty feet, as near's I could judge. It had red eyes, that glared like the tail-lamps of a train, and it spat fire, and it----" "Whoa! Whoa!" laughed Walt Phelps. "Now we know it was a nightmare, Pete. The dream of a rarebit fiend. You ate too much crackers and cheese at supper." "How was it we didn't see it?" asked Ralph, who had not spoken up till now.