Weber Bar

A Weber bar is a type of resonant mass gravitational wave detector designed to detect gravitational waves, devised and constructed by physicist Joseph Weber at the University of Maryland. Multiple of these devices were made, both of consisting of aluminium cylinders and stated to be 1.5 (5ft) meters in length, 0.6m (2ft) and 0.2m (8") in diameter, antennae for detecting gravitational waves. There... (Wikipedia)