From Alan Lightman’s 1993 book, Einstein’s Dreams:
In this world, time is like a flow of water, occasionally displaced by a bit of debris, a passing breeze. Now and then some cosmic disturbance will cause a rivulet of time to turn away from the mainstream, to make connection back stream. When this happens, birds, soil, people caught in the branching tributary find themselves suddenly carried to the past. (13-14)
Alan Lightman, Einstein’s Dreams. 1993. New York: Warner Books, 1994.