Buck goes through a few owners in Jack London's short novel.
1) Judge Miller
He is Buck's original owner. From the judge, Buck learns how to live the life of a ' sated aristocrat' dog. Half St. Bernard and half Scottish shepherd dog, Buck inherited size from his father, shrewdness and cunning from his mother. He domineers over the other dogs on the property, hunts with the judge's sons, takes walks with the judge's daughters, and carries the judge's grandsons on his back.
From this life of happiness and cherished existence, Buck is surreptitiously (secretly) sold by Manuel (the gardener's helper) to finance a gambling habit. After being transported by strange, unkempt men, first in a baggage car, then a truck on a ferry steamer, and finally on an express train, Buck is handed into the custody of the man in the red sweater.
2) The man in the red sweater
From the man in the red sweater, Buck learns to respect a primitive law: that a man with a club will never be defeated. After the man in the red sweater beats Buck senseless, Buck decides that although he will obey a man with a club, he will never conciliate or ingratiate himself towards such a tormenter. The man in the red sweater sells him to two French Canadians.
3) The two French Canadians, Perrault and Francois
The two men transport Buck and other dogs on a ship bound for Alaska. Buck will work as a sled dog delivering mail. Once landed, Buck finds himself in foreign territory, in a 'place of savages' who know 'no law but the law of club and fang.' This is the wild wilderness, and the weak will not only be vanquished but mercilessly crushed. When Curly, a friendly dog who traveled with him, tries to make friends with another husky, she is attacked by the husky without cause. After the husky brings her down, thirty or forty huskies spring in to batter her to death. Buck learns that a dog will never survive once downed; he resolves never to end up in that position.
From his days as a draught animal working for the French Canadians, he learns many things. Among other lessons, he learns how to steal food to keep from starving. 'Survival of the fittest' is the law in this forbidding Alaskan landscape, and Buck learns to adapt the cunning shrewdness he inherited from his mother to his new life.
Perrault and Francois travel with the dogs to Skaguay and there, hand the dogs over to a Scottish half-breed, who runs the dogs to their limit. He sells them to two men (Hal and Charles) and a woman (Mercedes) who further abuse him and his fellow dogs. When Hal almost clubs Buck to death, Thornton intervenes.
4) John Thornton
From Thornton, Buck learns that merciful owners do indeed exist in this cold, forbidding land. Thornton teaches Buck to trust humans again by first saving him from certain death, then nursing him back to health, and finally, letting Buck enjoy the companionship of his two other friendly dogs, Nig (a bloodhound mix) and Skeet (an Irish setter). In this loving atmosphere, Buck convalesces and grows strong once more. With Thornton, he develops his first passionate, loyal adoration for a human master who treats his animals as if they were his own children. Buck is free to be who he is, retaining both civilized and wild aspects of his unique doghood in Thornton's care.
Faithfulness and devotion, things born of fire and roof were his; yet he retained his wildness and wiliness.
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