Symbolism, Imagery, Allegory
Fireside Chat
Be forewarned: there are no s'mores at Buck's dream campfire. In fact, there's not a whole lot of food. Or anything else that even remotely represents civilization.
And that's because Buck dreams of sitting by a fire with a primitive caveman:
Sometimes as he crouched there, blinking dreamily at the flames, it seemed that the flames were of another fire, and that as he crouched by this other fire he saw another and different man from the half-breed cook before him. This other man was shorter of leg and longer of arm, with muscles that were stringy and knotty rather than rounded and swelling. The hair of this man was long and matted, and his head slanted back under it from the eyes. He uttered strange sounds, and seemed very much afraid of the darkness, into which he peered continually, clutching in his hand, which hung midway between knee and foot, a stick with a heavy stone made fast to the end. He was all but naked, a ragged and fire-scorched skin hanging part way down his back, but on his body there was much hair. In some places, across the chest and shoulders and down the outside of the arms and thighs, it was matted into almost a thick fur. He did not stand erect, but with trunk inclined forward from the hips, on legs that bent at the knees. About his body there was a peculiar springiness, or resiliency, almost catlike, and a quick alertness as of one who lived in perpetual fear of things seen and unseen. (4.24)
Buck longs to get in touch with his past, his ancestry, the great tradition of existing in the harsh wilderness. But because he's still a domesticated(ish) dog for most of the book, his daydreams take place in a ancient cave, with early man by his side. His visions increase in intensity as the novel progresses, suggesting that Buck is changing—he comes to long for the full moon howling routine more than the chewing slippers routine.
But we'd be remiss if we didn't mention another campfire: the campfire that Buck shares with Thornton. At first, Buck loves lounging around with his favorite Brawny Paper Towel Man-lookalike. But even that becomes stiflingly domestic:
So peremptorily did these shades beckon him, that each day mankind and the claims of mankind slipped farther from him. Deep in the forest a call was sounding, and as often as he heard this call, mysteriously thrilling and luring, he felt compelled to turn his back upon the fire and the beaten earth around it, and to plunge into the forest, and on and on, he knew not where or why; nor did he wonder where or why, the call sounding imperiously, deep in the forest. But as often as he gained the soft unbroken earth and the green shade, the love for John Thornton drew him back to the fire again. (6.11)
It's when Buck starts being lured beyond the confines of the campfire (and therefore beyond the confines of his life as a human companion) that you know that Buck is really becoming wild. One might almost say that he's becoming...Buckwild. (Sorry. We had to.)