Roman catapults

Catapults, in various forms, were used by many ancient civilisations to break down enemy defences and break sieges which were costly.  The Senior Science Club made catapults with soft drink cans held together with thick elastic bands.  The angle of the catapult arm (a kitchen fork) could be adjusted by changing the amount of buffer (two pencils taped together).  It was interesting to see how our adjustments to the angle of flight changed the distance projectiles travelled.