Geophone

The geophone, now often known as the ocean drum is a percussion instrument, invented by the French composer Olivier Messiaen for use in his large composition for piano and orchestra entitled Des canyons aux étoiles… ("From the canyons to the stars…") and later appeared in his other works. It consists of a drum filled with thousands of small lead pellets, and is played by swirling it around slowly so that the noise of the pellets resembles the sound of dry shifting earth.