As he spoke the last light of day vanished. Stars and a quarter moon leaped out in the swiftly darkening sky. The small fire of the expedition threw dim shadows against the poles of the night shelters. Lights glimmered in the Red Bone huts, and other lights began to streak across the gloom--the bright little lanterns of fireflies coasting along the stream. But at the point where the Red Bone night guard lurked no light shone. They had built no fire, and now they were almost invisible in the faint moonshine--sinister shadows which even now might be meditating murder or worse. Lourenço lounged over to Tucu, who was watching those shadows with a fixed cat stare, and informed him that until morning a man with a gun would be always on guard while the rest slept. The Indian grunted approval. By way of precaution against being killed by his own men, the Brazilian added the information that later on he and his comrade would leave the camp and go upstream for a time. At this Tucu's eyes dwelt on his, veered to the lights of the town, and returned. In them was a plain, though unspoken, question. The bushman ignored it and strolled back to his _tambo_. The moon sailed higher. The animal uproar of early night began to diminish. The fire, almost buried under slow-burning wood whose acrid smoke alleviated the insect pests, smoldered dull red. McKay and Knowlton drew lots for the first sleep, the captain winning and promptly getting under his net. In the Mayoruna shelter all was dark and silent, each man sleeping lightly with one hand on a weapon. The two Brazilians also were out of sight in their hut. Up and down, a barely distinguishable figure, Knowlton passed slowly with holster unbuttoned and rifle cocked, eyes turning periodically to the Red Bone outpost and ears intent to pick any unusual sound out of the night noise. Gradually the small lights of the town faded out. To all appearance, sleep had whelmed it for the night. The watchers on the farther shore stirred a little at times, but the blot they made in the moonshine remained fixed in the same spot. The only moving things were the khaki-clad sentinel and the blazing fireflies. Another hour rolled slowly by. The sentinel stopped and stood at a corner of the _tambo_. Now was as good a time as any for the Brazilians to start their perilous reconnaissance. Perhaps they had gone to sleep. He squinted at their hammocks. Yes, they were occupied. Stepping softly to the hammock of Pedro, he lifted the net to whisper to the occupant. Then he stared, dropped the net, and lifted Lourenço's curtain. A soft, self-derisive chuckle sounded in his throat as he stole out again.