Isabella is recounting her ride to the Hughes’ house. She’s just left Jim and continued into the storm.
“The fog grew darker and thicker, the day colder and windier, the drifts deeper; but Birdie, whose four cunning feet had carried me 600 miles, and who in all difficulties proves her value, never flinched or made a false step, or gave me reason to be sorry that I had come on.”
She really is the best horse.
Isabella trusts her to carry them through the blowing snow and drifts, trusting “the pony’s sagacity.* It failed for once, for she took me on a lake and we fell through the ice into the water… and had a hard fight back again…. I wrapped up my face, but the hard, sharp snow beat on my eyes - the only exposed part-bringing tears into them, which froze and closed up my eyelids at once.”
She takes a glove off to pry open each eye and pick the ice from it. She starts to wonder if this was a good idea and if she’s even heading the right direction anymore. If she doesn’t reach Longmount in the next 30 minutes, she realized, she’ll be so frozen that she’ll fall off of Birdie.