Here is the table top of the main controls of the Miraflores Locks.  When the little silver knobs are turned, they will open a set of gates or let water in or out of a chamber.  The red colored device in the immediate front is a locking device so no one touches these knobs.   There are vertical meters that show the depth of the water in the chamber.   What a neat set up.  We both got to turn one of the knobs during this transit.   Under close supervision of course.