Quotation from: White Fang

Written by: Jack London

Again he awakened, a little later, though it seemed hours to him. A
mysterious change had taken place--so mysterious a change that he was
shocked wider awake. Something had happened. He could not understand at
first. Then he discovered it. The wolves were gone. Remained only the
trampled snow to show how closely they had pressed him. Sleep was
welling up and gripping him again, his head was sinking down upon his
knees, when he roused with a sudden start.