Cochlea to structures in the brainstem for further processing. The "stapes" (stirrup) ossicle bone of the middle ear transmits vibrations to the "fenestra ovalis" (oval window) on the outside of the cochlea, which vibrates the perilymph in the "vestibular duct" (upper chamber of the cochlea). The ossicles are essential for efficient coupling of sound waves into the cochlea, since the cochlea environment is a fluid–membrane system, and it takes more pressure to move sound through fluid–membrane waves than it does through air; a pressure increase is achieved by the area ratio of the tympanic membrane to the oval window, resulting in
Jock Stirrup Jock Stirrup Marshal of the Royal Air Force Graham Eric Stirrup, Baron Stirrup, (born 4 December 1949), informally known as Jock Stirrup, is a former senior Royal Air Force commander who was the Chief of the Defence Staff from 2006 until his retirement in late 2010. He is now a Crossbench member of the House of Lords. In April 2013, he was appointed a Knight of the Order of the Garter by Queen Elizabeth II. As a junior RAF officer, Stirrup was a jet pilot, and saw action in the Dhofar War. Later in his career, he commanded No. 2