Despair's Last Journey by David Christie Murray

Paul Armstrong -- the real Paul Armstrong who dreamed these dreams of memory -- sat day by day in his mountain solitude surrounded by the smoke-fog which obliterated all but the nearer objects from his view. He could faintly distinguish the bluff on the other side of the canon. It was like a pale, flat, and barely perceptible stain on grayish-brown paper. The mountains were all abolished, but their ghostly voices lived. Here and there the slumbering heat upon their flanks would provoke a snow-slide, and the long-drawn roar and rumble of it would go rolling and echoing apparently in a dozen regions all at once, so that it would be impossible to tell from what direction the original sound proceeded. Two voices of the solitude were ceaseless -- the reverberating roar of the river and the chatter of the mountain brook which ran to meet it; but in ears long accustomed to them they seemed to weave a silence of their own.

Twice a day, at least, his sole reminders of the living, pulsing outer world went by. Sometimes as the panting train rushed east or west, its reminder of the world from which he had parted brought a bitter pang with it.