"Listen!" he said in low, gruff voice. He held out an open palm, three snail-shells in it, signifying that they should take one each. "Listen!" he repeated, and put the smallest shell against his own ear. "D'you hear that curious sound?" His head was cocked sideways, one ear pressed tight against the shell, the other open to the sky. "The Ganges..." he mumbled to himself after an interval, "but the stones are moving--moving in the river bed.... That long, withdrawing roar!" He was just about to add "down the naked shingles of the world," when Uncle Felix interrupted him. "Grating," he said, listening intently to his shell; "a metallic, grating sound. What is it?" There was apprehension in his tone, a touch of sadness. "It's getting louder too!" "Footsteps," exclaimed Tim. "Two feet, not four. It's _not_ a badger or a rabbit." He went on with sudden conviction--"and it's coming nearer." There was disappointment and alarm in him. "Though it might be a badger, p'r'aps," he added hopefully. "But I hear singing," cried Judy breathlessly, "nothing but singing. It's a bird." Her face was radiant. "It _is_ a long way off, though," she mentioned. They put their shells down then, and listened without them. They glanced from one another to the sky, all four heads cocked sideways. And they heard the sound distinctly, somewhere in the air about them. It had changed a little. It was louder. It _was_ coming nearer. "Metallic," repeated Uncle Felix, with an ominous inflection. "Machinery," growled Stumper, a fury rising in his throat. "Clicking," agreed Tim. He looked uneasy. "I only hear a bird," Judy whispered. "But it comes and goes--rather." And then the Tramp, still lying beside his little fire of burning sticks, put in a word. "It's _we_ who are going," he said in his singing voice. "We're moving on again." They heard him well enough, but they did not understand quite what he meant, and his voice died into the distance oddly, far away already, almost on the other side of the fence. And as he spoke they noticed another change in the world about them. Three of the party noticed it--the males, Uncle Felix, Tim, and Come-Back Stumper. For the light was fading; it was getting darker; there was a slight sense of chill, a growing dimness in the air. They realised vaguely that the Tramp was leaving them, and that with him went the light, the heat, the brilliance out of their happy day.