Under ordinary circumstances, Has-se's Indian instinct would not have permitted him to cross the open water of the bayou in broad daylight when he suspected that an enemy might be lying in wait for him on its farther side. On this occasion, however, it seemed so impossible that the occupants of the canoe, of which he had caught but the merest glimpse, should have looked back and detected them at the same instant, that he decided to push on, and if possible discover more of it. So he and Rene crossed the open water as quickly and with as little noise as possible, and as they approached its opposite side, Has-se gazed keenly into the dark lanes between the moss-hung cypresses. He neither saw nor heard anything to cause him alarm, and congratulating themselves that they had not been discovered, the boys pushed on over waters of another extremely narrow stream. This, to Rene's surprise, flowed, though with an almost imperceptible current, in the direction they were taking, or exactly opposite to that of the river they had ascended from the salt-marshes of the east. As Has-se had requested him to keep absolute silence, and on no account to speak, he restrained his curiosity for the present, but determined to seek an explanation of this phenomenon when an opportunity should offer. He afterwards discovered that the river they had ascended, and that they were now descending, both rose in the great swamp, and that their headwaters were connected by navigable streams, but that while one flowed east into the Atlantic, the other flowed west into the Gulf of Mexico. In thus deeming themselves undiscovered by those in advance of them, the boys made an almost fatal mistake. The wily Cat-sha, accustomed to look for danger behind every tree, and almost expecting to hear the war-cry of his enemies in every breath of wind, knew better than to leave open waters without looking behind as he did so. On this occasion the quick glance thrown backward at the instant his canoe entered the shadows of the cypresses detected the gleam of a paddle, and he knew at once that he and Chitta were being followed, even as they were following Micco and his people. He said nothing until they were safely within the shadows, when he told Chitta of his discovery. The latter advised going into hiding at once, and awaiting the approach of their unknown pursuers; but the more experienced Cat-sha said no, for if they had also been discovered, that was exactly what they would be expected to do, and their pursuers would exercise more than a usual amount of caution in approaching that point. Once safely past it they would advance more boldly, thinking that their own presence had been undetected. He therefore continued on down the little stream for nearly a mile, until they reached a point where the channel was so seriously obstructed by overhanging vines and stranded driftwood that only a passage barely wide enough for a single canoe was left open.