Squaring the circle: the areas of this square and this circle are both equal to Ï. In 1882, it was proven that this figure cannot be constructed in a finite number of steps with an idealized compass and straightedge.
Not to be confused with Cloud top. In aviation, ceiling is a measurement of the cloud base height relative to the ground. Ceiling is reported as part of the METAR (METeorological Aviation Report) used for flight planning by pilots worldwide. A ceiling listed as unlimited means either that the sky is mostly free of cloud cover, or that the cloud is high enough not to impede Visual Flight Rules (VFR) operation. In a METAR, the lowest BKN or OVC layer specifies the cloud ceiling.
Definition: In architecture, a coffer is a sunken panel in a ceiling (including the interiors of domes and vaults). The word comes from the ancient Greek word kophinos, which means basket..The Latin word for basket, cophinus, was adopted by the old French to mean various types of hollowed containers.he Latin word capsa, meaning box, evolved into the words caisson (an ammunition chest) and casket (same as coffin). Caisson ceiling is sometimes used to describe this type of ceiling hollow. The Chinese name for this type of ceiling, zaojing, means a well for plants that grow in water.