Besides Welby he saw no living creature. The camp was hidden from him completely by the trees and bushes, and they were so quiet within the circle of the wagons that no sound came from them. An hour passed. It became two, then three. Vaporous clouds floated by the moon. The silver light on the river waned. The current became dark yellow again, but flowing as ever with that soft, swishing sound. The change affected Phil. The weird quality of the wilderness, clothed in dark, made itself felt. He was glad when he met Welby, and they lingered a few seconds longer, talking a little. He came back once more to the river, now flowing in a torrent almost black between its high banks.

He took his usual long survey of the river, both up and down stream. Phil was resolved to do his full duty, and already he had some experience, allied with faculties naturally keen. He examined the opposite bank with questioning eyes. At first it had seemed a solid wall of dark green, but attention and the habit of the darkness now enabled him to separate it into individual trees and bushes. Comanches ambushed there could easily shoot across the narrow stream and pick off a white sentinel, but he had always kept himself well back in his own bushes, where he could see and yet be hidden.

His gaze turned to the river. Darker substances, drift from far banks, still floated on its surface. The wind had died. The branches of the trees did not move at all, and, in the absence of all other sound, the slight swishing made by the flowing of the river grew louder. His wandering eyes fastened on a small stump that was coming from the curve above, and that floated easily on the surface. Its motion was so regular that his glance stayed, and he watched it with interested eyes. It was an independent sort of stump, less at the mercy of the current than the others had been. It came on, bearing in toward the western bank, and Phil judged that if it kept its present course it would strike the shore beneath him.

The black stump was certainly interesting. He looked farther. Four feet behind it was floating another stump of about the same size, and preserving the same direction, which was a diagonal line with the current. That was a coincidence. Yet farther was a third stump, showing all the characteristics of the other two. That was remarkable. And lo! when a fourth, and then a fifth, and then a sixth came, a floating line, black and silent, it was a prodigy.

The first black stump struck lightly against the bank. Then a Comanche warrior, immersed hitherto to the chin, rose from the stream. The water ran in black bubbles from his naked body. In his right hand he held a long knife. The face was sinister, savage, and terrible beyond expression. Another of the stumps was just rising from the stream, but Phil fired instantly at the first face, and then sprang back, shouting, "The Comanches." He did not run. He merely sheltered himself behind a tree, and began to reload rapidly. Welby came running through the bushes, and then the others, drawn by the shout. In a minute the timber was filled with armed men.

"What is it? What is it? What did you shoot at?" they cried, although the same thought was in the minds of every one of them.

"The Comanches!" replied Phil. "They came swimming in a line down the river. Their heads looked like black stumps on the water! I fired at the first the moment he rose from the stream! I think it was their plan to ambush and kill the sentinels!"

Bill Breakstone was among those who had come, and he cried:

"Then we must beat them off at once! We must not give them a chance to get a footing on the bank!"

They rushed forward, Phil with them, his rifle now reloaded, and gazed down at the river. They heard no noise, but that slight swishing sound made by the current, and the surface of the stream was bare. The river flowed as if no foreign body had ever vexed its current. Fifty pairs of eyes used to the wilderness studied the stream and the thickets. They saw nothing. Fifty pairs of ears trained to hear the approach of danger listened. They heard nothing but the faint swishing sound that never ceased. A murmur not pleasant to Phil, arose.