The World under the Rainbow is the fictional setting for the book As Blue As the Sea (Russian Синий как море, Sinij kak more) by Russian fantasy author Alexander Laik (Александр Лайк). The number 8 is considered sacred by the nations under the Rainbow (originally there were eight nations/races that corresponded to the eight sacred colours: red, orange, yellow, green, cyan, blue, violet, and white), thus they use octal notation (the book describes the octal system of units similar to metric system). Preference of number eight is reflected in the calendar as well (so called "The New Calendar").