Geophone (musical instrument) Geophone (musical instrument) The geophone 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…"). 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. Messiaen commissioned a Parisian instrument maker to construct one to his design, and he carried this instrument worldwide to early performances of the piece (which was given its first
Department of Defense Dictionary of Military and Associated Terms Department of Defense Dictionary of Military and Associated Terms The Department of Defense Dictionary of Military and Associated Terms is a compendium of terminology used by the United States Department of Defense (DOD). It sets forth standard US military and associated terminology to encompass the joint activity of the Armed Forces of the United States in both US joint and allied joint operations, as well as to encompass the Department of Defense (DOD) as a whole. These military and associated terms, together with their definitions, constitute approved DOD terminology for general use by all components of the Department of Defense.