But as if impelled by a hidden force he had never felt before, Baldy sturdily forged on and on, till they, too, were left behind. A new fervor thrilled him as he determined to show that he was more than "just dog." No understudy on the stage, given an unexpected opportunity, ever desired more ardently to eclipse the star than did Baldy to fill poor Kid's place. How they flew over the ground; how exhilarating the air; how light the sled. And then it suddenly dawned upon Baldy that the sled was too light. When Allan was not running behind with a tight grasp on the handle-bars, he was usually perched at the back on the projecting runners; and for some time the dog had not noticed this additional weight. Then, too, he was beginning to miss his master's voice--"Hi, there, Tom, Dick, Harry, snowbirds in sight; rabbits, Spot; road house, Barney." Of course all of the dogs knew perfectly well that it was only a joke; that snowbirds, rabbits and road houses are things that do not concern you at all when you are being driven in a race. But they enjoyed the little pleasantry, nevertheless, and it gave them delightful subjects to think about that might become possibilities when they were not in harness. If "Scotty" was not addressing them personally, he was often singing bits of Scotch ballads, or whistling scraps of rag-time, which was wonderfully cheering, and gave them a sense of companionship with him. At last the instinct that all was not right was too strong for Baldy. Stopping suddenly, he looked back and discovered that they were driverless. He realized that such halts were most unwise; but the team without Allan was as a ship without a Captain and to Baldy there was but one thing to do--to find "Scotty" at all hazards. For an instant there was danger of a mutiny amongst the dogs. Tom, Dick and Harry tacitly agreed that it was a marvelous chance to make that snowbird joke a charming reality; there was a stirring of McMillan's fiery blood, for he still admitted but one source of control; a plump fluffy hare, scurrying by within range of Spot's young eyes inspired him with a desire to give chase, as once again he quite forgot the grave importance of filling a position in a racing team. But Baldy, knowing that the time for action had come, that his supremacy as a leader must be acknowledged, and at once, firmly held his ground. Turning, he faced them fearlessly. There was a low ominous growl, a smouldering light in his strange, somber eyes, a baring of his sharp white fangs. Yet it was something else, a something in the very nature of the dog, in his steadfast spirit, his indomitable will, that made the others feel in some subtle, final way that they must obey him. So when he swung round they followed him as unswervingly as they would have followed Kid.