To look at the river was to court terror, but I had to look. It was an infernal thing. It roared in hollow, sullen voice, as a monster growling. It had voice, this river, and one strangely changeful. It moaned as if in pain—it whined, it cried. Then at times it would seem strangely silent. The current as complex and mutable as human life. It boiled, beat and bulged. The bulge itself was an incompressible thing, like a roaring lift of the waters from submarine explosion. Then it would smooth out, and run like oil. It shifted from one channel to another, rushed to the center of the river, then swung close to one shore or the other. Again it swelled near the boat, in great, boiling, hissing eddies.
-- Zane Grey, The Last of the Plainsmen, describing the Colorado River