to build a fire by jack london

From the text:

The Yukon lay a mile wide and hidden under three feet of ice. On top of this ice were as many feet of snow. It was all pure white. North and south, as far his eye could see, it was unbroken white. The one thing that relieved the whiteness was a thin dark line that curved from the pine-covered island to the south. It curved into the north, where it disappeared behind another pine-covered island. This dark line was the trail—themain trail.