How many pounds must Buck start on a sled to win the bet against Matthewson?

To win the bet against Matthewson, Buck must pull a sled loaded with 1,000 pounds. This amount is significant because it showcases Buck's incredible strength and resilience, which have been developed through his challenging journey in the harsh wilderness. By pulling a load of this size, Buck demonstrates not only his physical capabilities but also his determination to succeed in a high-stakes situation. Throughout "The Call of the Wild," Buck faces numerous challenges that push him to his limits, and this particular challenge underscores his evolution from a domesticated pet to a robust and powerful creature of the wild. The weight of 1,000 pounds serves as a testament to his growth, reflecting the central themes of survival and adaptation in the novel.