Over they went, up to their necks in the boiling foam, and not a second too soon, for Ken could hold the boat no longer. It went over smoothly, just dipping the stern under water. If the boys had remained aboard, the boat would have swamped. As it was, Pepe managed to catch the rope, which Ken had wisely thrown out, and he drifted down to the next ledge. Ken found this nearly as high as the last one. So he sent the boys below to catch the boat. This worked all right. The shelves slanted slightly, with the shallow part of the water just at the break of the ledge. They passed half a dozen of these, making good time, and before they knew it were again in a deep, smooth jungle lane with bamboo and streamers of moss waving over them. The shade was cool, and Ken settled down in the stern-seat, grateful for a rest. To his surprise, he did not see a bird. The jungle was asleep. Once or twice Ken fancied he heard the tinkle and gurgle of water running over rocks. The boat glided along silently, with Pepe rowing leisurely, George asleep, Hal dreaming. Ken watched the beautiful green banks. They were high, a mass of big-leafed vines, flowering and fragrant, above which towered the jungle giants. Ken wanted to get out and study those forest trees. But he made no effort to act upon his good intentions, and felt that he must take the most of his forestry study at long range. He was reveling in the cool recesses under the leaning cypresses, in the soft swish of bearded moss, and the strange rustle of palms, in the dreamy hum of the resting jungle, when his pleasure was brought to an abrupt end. “Santa Maria!” yelled Pepe. George woke up with a start. Hal had been jarred out of his day-dream, and looked resentful. Ken gazed about him with the feeling of a man going into a trance, instead of coming out of one. The boat was fast on a mud-bank. That branch of the river ended right there. The boys had come all those miles to run into a blind pocket. Ken’s glance at the high yellow bank, here crumbling and bare, told him there was no outlet. He had a sensation of blank dismay. “Gee!” exclaimed Hal, softly. George rubbed his eyes; and, searching for a cigarette, he muttered: “We’re lost! I said it was coming to us. We’ve got to go back!” *XI* *AN ARMY OF SNAKES* For a moment Ken Ward was utterly crushed under the weight of this sudden blow. It was so sudden that he had no time to think; or his mind was clamped on the idea of attempting to haul the boat up that long, insurmountable series of falls. “It’ll be an awful job,” burst out Hal. No doubt in the mind of each boy was the same idea--the long haul, wading over slippery rocks; the weariness of pushing legs against the swift current; the packing of supplies uphill; and then the toil of lifting the heavy boat up over a fall.