At the man’s heels trotted a dog, a big native husky, the proper wolf-dog, grey-coated and without any visible or temperamental difference from its brother, the wild wolf. The animal was depressed by the tremendous cold. It knew that it was no time for travelling. Its instinct told it a truer tale than was told to the man by the man’s judgment. In reality, it was not merely colder than fifty below zero; it was colder than sixty below, than seventy below. It was seventy-five below zero. Since the freezing-point is thirty-two above zero, it meant that one hundred and seven degrees of frost obtained. The dog did not know anything about thermometers. Possibly in its brain there was no sharp consciousness of a condition of very cold such as was in the man’s brain. But the brute had its instinct. It experienced a vague but menacing apprehension that subdued it and made it slink along at the man’s heels, and that made it question eagerly every unwonted movement of the man as if expecting him to go into camp or to seek shelter somewhere and build a fire. The dog had learned fire, and it wanted fire, or else to burrow under the snow and cuddle its warmth away from the air. The frozen moisture of its breathing had settled on its fur in a fine powder of frost, and especially were its jowls, muzzle, and eyelashes whitened by its crystalled breath. The man’s red beard and moustache were likewise frosted, but more solidly, the deposit taking the form of ice and increasing with every warm, moist breath he exhaled. Also, the man was chewing tobacco, and the muzzle of ice held his lips so rigidly that he was unable to clear his chin when he expelled the juice. The result was that a crystal beard of the colour and solidity of amber was increasing its length on his chin. If he fell down it would shatter itself, like glass, into brittle fragments. But he did not mind the appendage. It was the penalty all tobacco-chewers paid in that country, and he had been out before in two cold snaps. They had not been so cold as this, he knew, but by the spirit thermometer at Sixty Mile he knew they had been registered at fifty below and at fifty-five. He held on through the level stretch of woods for several miles, crossed a wide flat of nigger-heads, and dropped down a bank to the frozen bed of a small stream. This was Henderson Creek, and he knew he was ten miles from the forks. He looked at his watch. It was ten o’clock. He was making four miles an hour, and he calculated that he would arrive at the forks at half-past twelve. He decided to celebrate that event by eating his lunch there.