What metaphors are used in The Dharma Bums by Jack Kerouac?

In Chapter Twelve, Kerouac concludes his extended allegory of mountain climbing. Ray's fear of the summit gives way to an ecstatic epiphany when he realizes that Japhy has reached the summit, and he realizes that the continued climbing after the peak is not falling but returning. Thereafter, he loses all fear of falling from the great height, and rather than inch along when nearing drops and crags, he leaps and bounds down the mountain full of excited confidence. Through this experience, Ray has turned a metaphorical corner in his development as a character. His old life will fade in the distance as he sets out on a new path.