" I went down from the house in that hour, wearing the wet suit I use for tropical diving…since that day I have walked in the river in all seasons except late fall, winter, and early spring, when the water is too high…I’ve walked up and down it on moonlit nights, and on nights of the new moon when the only light falling in the woods has come from the bulb above my desk, that and photons from the stars above, the suns Ishmael imagined as islands in a “continentless,” continuous sea. Crabbing upcurrent some evenings, feeling the force of the water on my legs and a night breeze in my face, I often think of myself as passing the house offshore. Up there in that room, as I see it, is the reading and the thinking-through, a theory of rivers, of trees moving, of falling light. Here on the river, as I lurch against a freshening of the current, is the practice of rivers. In navigating by the glow of the Milky Way, the practice of light. In steadying with a staff, the practice of wood. "