It is no coincidence that there is only one geographer in the Roman period writing in Latin: Pomponius Mela. The Roman statesman was generally not interested in science for its own sake; rather, scientific knowledge served political and technological functions. Geography and ethnography were tools of imperialism and the expansion of Roman rule. Historians such as Livy and Tacitus, and prominent statesmen such as Julius Caesar- and Augustus, wrote works that contained geographical and ethnographical data, but their main concern was the political usefulness of this -information. Caesar's descriptions of the Gallic tribes as fierce, unfaithful, and undisciplined serve a particular end: they justify the conquest of Gaul. Caesar reports, for example, that the tribes living in the interior of Britain do not farm, but live instead on milk (not unlike the mythological' Cyclopes, the savage giants in Homeric epic). When his report...