Ministry of Defence Main Building (United Kingdom) each and cost £12,600. Similar figures representing "air" and "fire" were intended to be installed at the south end of the building, however these were never constructed. During the 1950s, building staff nicknamed the statues "Mr and Mrs Parkinson", after Cyril Northcote Parkinson, the Board of Trade civil servant who devised Parkinson's Law which states "work expands so as to fill the time available for its completion". More recently MOD staff refer to the statues as the "two fat ladies". The badge of the RAF is carved into stone columns either side of the southern entrance to the building, reflecting
Entropy (arrow of time) the speeds and locations of the different particles are completely random, up to the need to conform with the macrostate of the system). This is closely related to the Second Law of Thermodynamics. Take for example (experiment A) a closed box that is, at the beginning, half-filled with ideal gas. As time passes, the gas obviously expands to fill the whole box, so that the final state is a box full of gas. This is an irreversible process, since if the box is full at the beginning (experiment B), it does not become only half-full later, except for the very