We left Iquitos in the afternoon on a slow boat bound for Pebas, the deck slick beneath bare bulbs and hammocks slung wherever two uprights could be found. Men played casino for small coins on an upturned crate while children slept above them. The river police stopped us several times, coming aboard with torches and rifles to inspect papers, passengers and freight. Each time we got under way again, the engine rumbled awake like some terrible giant, and the boat moved east into darkness broken only by settlement fires, heat lightning and the moon-silvered Amazon.