TARDIS were not, its weight would shatter the Earth's surface. In the tie-in novels, the interior of the TARDIS has been known to contain an entire city, encompass an entire parallel Earth, and even dwarf Gallifrey itself when turned inside out. A distinctive architectural feature of the TARDIS interior is the roundel. In the context of the TARDIS, a roundel is a circular decoration that adorns the walls of the rooms and corridors of the TARDIS, including the console room. Some roundels conceal TARDIS circuitry and devices, as seen in the serials "The Wheel in Space" (1968), "Logopolis", "Castrovalva" (1981), "Arc
Royal Air Force roundels roundels for all aircraft was seen on the overall NIVO (dark green) painted night bombers (e.g., Handley Page Heyfords) which used type B roundels. Roundels used on aircraft painted in NIVO were duller than the normal colours. The size of the roundel was generally determined by the space available at the specified location, with a space of several inches around the edges. Some aircraft - primarily seaplanes, had a white outline around the fuselage roundel, even on silver doped finishes however this application was inconsistent so was probably not official. From 1929, the RAF switched to a new system of