By Peter Anderson Row, row, row your boat. Row it because El Rio is running high with water that has just come down off the mountain and your friends want to take their little boy on his first float; row it so he feels the waves as they push up against the floor of the raft, so that a small wave over the bow will surprise him—yes, this river still remembers the high snowfields; row it so he can see how the river gives itself away, parting ways around an island, then gathering itself up into swirls and eddies on…