The other shot we need to take for the "Old Man, Old Woman" folktale was tossing a rock into the water.  You can guess where this might be going.  So I had all these large pieces of volcanic rock which were pretty light and so easy to toss.  Unfortunately they occasionally floated.  The other problem was the ducks who got very interested in what we were doing and got into our shot.  I lost a lot of my rocks chasing the ducks away.