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From then on, night and day, Buck never left his prey, never gave it a moment’s rest, never permitted it to browse the leaves of trees or the shoots of young birch and willow. Nor did he give the wounded bull opportunity to slake his burning thirst in the slender trickling streams they crossed. Often, in desperation, he burst into long stretches of flight. At such times Buck did not attempt to stay him, but loped easily at his heels, satisfied with the way the game was played, lying down when the moose stood still, attacking him fiercely when he strove to eat or drink.