He had come upon a lake under the moon and stood a while at its side, long enough to feel afloat in the way of that slim tree branch he was watching drift on down the water.  It stunned him to consider that the lake may instead be a river.  It was flowing unseen; and, in the focus it took to see, that branch began to take on the look of a boy floating, floating from his boyhood bed all the way to the moon in order to take a look back.  He stood at the lake now, decades later, and took again that journey, and turned by habit when he imagined himself at the moon.  A faint weakness swelled so alarmingly in him that he quickly retreated to his car and got on the road.  His look back from the moon had fallen not as always on Earth in its complete wholeness, but on that branch, which, softened now by the water, lay weightless on what looked a lake but ran as a river.