Just a pebble in the water; just a splash and it is gone;
but there's half-a-hundred ripples circling on and on,
spreading, spreading, from the center, flowing on out to the sea
and there's no way of telling where the end is going to be....
--An unattributed quotation found in the chapbook of U.S. Army nurse Frances Slanger, who was killed in Belgium in October, 1944 by German artillery fire. From the book American Nightingale by Bob Welch.
Update: The quotation is by James W. Foley (1874-1939). You can read the whole poem here.