The rest of mankind was as nothing.

Chance travellers might praise or pet him; but he was cold under it all, and from a too demonstrative man he would get up and walk away.

When Thornton's partners, Hans and Pete, arrived on the long-expected raft, Buck refused to notice them till he learned they were close to Thornton; after that he tolerated them in a passive sort of way, accepting favors from them as though he favored them by accepting.

They were of the same large type as Thornton, living close to the earth, thinking simply and seeing clearly; and ere they swung the raft into the big eddy by the saw-mill at Dawson, they understood Buck and his ways, and did not insist upon an intimacy such as obtained with Skeet and Nig.
For Thornton, however, his love seemed to grow and grow.

He, alone among men, could put a pack upon Buck's back in the summer travelling.