Sick Heart River by John Buchan — Read

They soon picked up the tracks of their forerunners in the long spouts of gravel, and as they slowly zigzagged downhill to the tree line the weather changed. The cold blue sky beyond the mountains dulled to a colder grey and all light went out of the landscape. It was like the coming of the Polar Night of which he had read, the inexorable drawing down of a curtain upon the glory of the world. The snow began to fall in big flakes, not driven by any wind, but like the gentle emptying of a giant celestial bin. Soon there was nothing but white round them, except the tops of the little gnarled firs.

Luckily they had reached the tree line before the snow began, for otherwise they might have lost the trail. As it was, Johnny soon picked it up from the blazes on the diminutive trunks. It led them down a slope so steep that it was marvellous that any roots could cling to it. They had to ford many ice-cold streams, and before they reached flat ground in the evening Leithen was tottering on the very outside edge of his strength. He scarcely heard Johnny's mutter, "Looks like Lew has lost his pal. Here's where he camped and there's just the one set of tracks. " He was repeating to himself Whitman's words like a prayer.