We have now traced on a spherical surface the area in which we say the inhabited world is situated; and the man who would most closely approximate the truth by constructed figures must necessarily take for the earth a globe like that of Crates, and lay off on it the quadrilateral, and within the quadrilateral put down the map of the inhabited world. But since the need of a large globe, so that the section in question (being a small fraction of the globe) may be large enough to receive distinctly the appropriate parts of the inhabited world and to present the proper appearance to observers, it is better for him to construct a globe of adequate size, if he can do so; and let it be no less than ten feet in diameter.