This machine was created by Ridgeway Banks in the 1970s at the University of California and given to my father, Edwin McMillan, who encouraged him to work on it. It works by putting very hot water in one side and very cold in the other. The metal loops hanging from the bars expand in one and contract in the other causing them to make the wheel turn. This continues as long as the water stays hot and cold... hmmm well maybe not so perpetual after all. For more information on the machine, check this out: http://www.richmondcarotary.org/newsletter/archive/2003and2004/flywheel_insert_Sep_26_2003.html For more about my father, look here: http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/mcmillan-bio.html