Hence it is that the inhabitants of the east do not see those eclipses of the sun or of the moon which occur in the evening, nor the inhabitants of the west those in the morning, while such as take place at noon are more frequently visible[1]. We are told, that at the time of the famous victory of Alexander the Great, at Arbela[2], the moon was eclipsed at the second hour of the night, while, in Sicily, the moon was rising at the same hour. The eclipse of the sun which occurred the day before the calends of May, in the consulship of Vipstanus and Fonteius[3], not many years ago, was seen in Campania between the seventh and eighth hour of the day; the general Corbulo informs us, that it was seen in Armenia, between the eleventh and twelfth hour[4]; thus the curve of the globe both reveals and conceals different objects from the inhabitants of its different parts. If the earth had been flat, everything would have been seen at the same time, from every part of it, and the nights would not have been unequal; while the equal intervals of twelve hours, which are now observed only in the middle of the earth, would in that case have been the same everywhere.