《汉书·志·五行志上》
然而水的大数就是六了，火的大数是七，木的大数是八，金的大数是九，土的大数是十。
然则水之大数六，火七，木八，金九，土十。
However, the large number of water is six, the large number of fire is seven, the large number of wood is eight, the large number of metal is nine, and the large number of earth is ten.