In message <E0xwBLb-00030a-00@dewey.mindlink.net> cyclops@mindlink.bc.ca (cyclops) writes: > you seem to be describing the piston motion as following a square-wave > motion. Anyone achieving square-wave motion of a non-zero mass should seek out their nearest physicist and ask then to sit down before describing their achievement. -- Phil Payne Committee Member, UK Audi [ur-]quattro Owners Club