Meanwhile the river had not been idle. Barney had left the white target at the foot of the big gum-tree on which it was to be nailed; but the river had evidently desired the piece of bank on which that gum-tree stood, and had undermined it. It had cracked off fifty feet back of the tree, and an acre at more had slumped down about four feet. There it had stopped, but Barney knew that the slightest jar might be enough to start the whole piece settling again beneath the river. Did he dare jump down on it, run out, get his target, and scramble back? Did he dare? Barney thought about false beacons, and scarcely hesitated. The bank on which he stood had cut away as sharply as if chiseled, and the soil that formed the edge was still wet and smooth. Over it slipped Barney to the lower part, and hastened toward the gum. He had just reached it when he felt a peculiar trembling of the earth, and heard a series of loud splashes at the waterside. A quick glance told him what was happening. The whole loose segment on which he stood had started slipping again. It went slowly down, while Barney raced for the firm bank; but when he reached the edge of the slipping piece he was already confronted by a precipice at least fifteen feet in height, to scale which was impossible. Badly frightened, but not panic-stricken, he made two or three futile attempts, only to bring the earth crashing down with him; and realizing that this was to invite immediate sinking of the part he stood on, he looked for another plan. Up- and down-stream ran the precipice which balked him. All round the other sides the land gave sharply down into the river, and at its feet washed that swift current, which, within a short distance of the edge, was seventy feet deep. Barney went carefully back to the big gum-tree, wondering how he would get off. As he stood by it the earth slipped five or six feet lower, and Barney realized that another six feet would put him under water. Then he had an idea. There was one route to possible safety—up the big gum-tree! Sometimes when the bank goes in, such trees roll over and drift away, their roots free of earth. Sometimes they turn their roots up, embed their branches in the bottom, and form dangerous snags. But sometimes they stand upright for days, even weeks, their tops out of water, their main trunk and roots hidden deep beneath the flood. This was going down so straight that Barney hoped it might take that course. It was a big tree and the nearest fork was at least twenty feet up. But Barney had brought his hammer and a pocketful of four-inch nails for the target. He picked the target up, and with two of them nailed it firmly to the tree five feet above the ground. He took a cord from his pocket and hung his lantern over his shoulder, drove a spike two feet from the ground for a step, mounted on it and threw a knee over the target, and drove another two feet above that.