After the man traveling alone with only a dog breaks through a wet spot as he continues his trek following his lunch, he wets himself halfway to the knees. Now, he must build a second fire to dry his feet or he will be lost to frostbite and death. Struggling with frozen fingers to untie the laces, the man realizes that he must cut them with his knife.
But before he could cut the strings it happened. It was his own fault, or, rather, his mistake. He should not have built the fire under the spruce tree.
Because the man "lacked imagination" and has no instinct of things, he does not anticipate that the fire under the spruce tree laden with snow will cause the snow to melt and fall into his fire, quenching the flames. Each time he has pulled a twig from under this tree, he has slightly moved branches and has created "an imperceptible agitation" that is "sufficient to bring about disaster." This act is the man's nemesis. Because he has not traveled with another man as the old man advised, there is no one to help him. Now he hears "his own sentence of death" in an uncaring nature of which he has been ignorant, unlike the dog whose instincts have told him it was too cold to be out.
When he breaks through the ice where a spring flowed and bubbled on top of the ice, yet hidden under the snow, he becomes wet to the knees. In a hurry to get the fire going, the man forgot to build the fire in an open space. He built the fire under a tree. As the fire grew, the snow from the tree branches melted and an avalanche occurred and the fire was put out by the falling snow. After this, he could not get a continuous fire going. After the fire went out, the man began to freeze. He is freezing to death. No doubt, he will die in the cold.
If only the man had listened to the old-timer of Sulpher Creek who warned him not to travel alone when it was that cold. Instead, the man thought of the old-timer as womanish. As he is dying, freezing to death in the snow, the man probably wishes he had listened to the old-time from Sulpher Creek.