Like a Scene From Metropolis

We saw a great thing this morning when getting on the ferry. Wendy is going to L.A. for an animation conference, so she boarded the ferry with me. We were walking toward the overhead bridge and we could see the sunlight streaming through it and the sillhouettes of people slowly boarding inside. Just beyond that, a huge raft with a crane aperatus was pounding a pylon into the harbor with a monotonous clang. Wendy said that it looked like a scene out of Metropolis. We got on the boat in a booth where we could see them driving the pylons down into the seabed. A big steel piston would be lifted in this tube and then come down on the pylon and drive it about four inches with each pound. We couldn't figure out what was lifting the piston, though. A small, dirty cloud of gas would displace from the side with every downstroke, and the piston would fly up again. Wendy speculated that some kind of charge was sending the piston back, but I'm not sure.