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 plans could be afforded over the coming years. The planning for the invasion of Iraq required new equipment and Stirrup became increasingly involved in planning for urgent operational requirements. A particular difficulty faced by Stirrup was the need to place equipment orders with industry before the Government was prepared to publicly commit to the action. Stirrup briefed ministers on this point but was prevented from placing the orders according to his desired timescale. In the end some critical items such as body armour, boots and desert clothing were not available to all the personnel who needed them when they deployed.