different kind from that diffused among the people, and every one might for himself acquire a certain range of knowledge. Some persons who had travelled in distant lands possessed an extensive knowledge of countries, and those anxious to learn derived their information from them. It is therefore generally impossible to say how much geographical knowledge an otherwise well educated man may have possessed. That which in later times was to be found in books which were generally read, was known also to every well-read Greek. But the living knowledge among the people was far more extensive Herodotus became acquainted in Scythia with people who had made distant journeys, or had heard accounts from others extending as far as the Ural mountains; and in like manner, others who visited Massilia might have obtained equally accurate information from people that visited Britain; such knowledge, however, was not generally diffused, but was possessed only by navigators and some others. All knowledge was purely practical, until some curious inquirer in some much frequented port collected the scattered information, put together all the περίοδοι and περίπλοι, and thus formed a geography. Eratosthenes lived in a large port town, and possessing an extensive library, he was the first to draw up a general ethnography; before he wrote his work, the geographical knowledge of one man was immensely different from that of another. The early Greeks and Asiatics entertained the notion that the earth was a circular plain, floating in the middle between heaven above and the nether world below. And this was the most natural conception: where there is no cause for assuming any other form, the circular is the most probable. The notion of Homer evidently is, that the plain is somewhat depressed in the centre, forming a basin in which the waters of the Mediterranean are collected, and that the world-river Oceanus flows round the upper edge of the plain. This opinion prevailed for a long time; it was entertained by Hecataeus as well as by Homer.