1. scree (10): n. loose rocks on the side of a mountain.
2. dementia (12): n. severe brain disorder.
1. "So Mortenson lay beneath the stars salting the sky" (12; ch. 1). It's a metaphor, because he is comparing salt crystals to stars, because they are both small white dots.
2. "'It was like hanging from a rope strapped to a big sack of potatoes'" (14; ch. 1). This is a simile. Etienne was unconscious, so he wasn't helping them at all.
3. "Mortenson gathered a comet's tail as he passed into tawny fields..." (24; ch. 2). It is a metaphor. He is comparing the children that were following him to a comet's tail.