THE GRECO-ROMAN PERIOD 95 



Geographical and ethnographical studies were much 

 in favour amongst the Romans. Sallustus and Caesar 

 give interesting information, the former on Northern 

 Africa, the latter on Gaul. Tacitus describes Great 

 Britain and particularly Germany and Scandinavia. 

 In the only mention he makes of astronomical subjects, 

 he shows how little the cultured Romans knew, for 

 he explains the light of the polar nights by the flatness 

 of the outermost countries of the earth, thus forgetting 

 what had been a commonplace of knowledge in Greece 

 for several centuries, to wit, the rotundity of our globe 

 (Agricola, ch. 12). It is evident that the Romans did 

 not study geography for its own sake, though we must 

 except Pomponius Mela (first century a.d.) who 

 utilized in a small but excellent text-book the statistical 

 material collected by Agrippa. 



2. GREEK SCIENCE IN THE EAST 



Thanks to the power of tradition, intellectual activity 

 was maintained, in spite of unfavourable conditions, 

 simultaneously in Greece, Egypt and Asia Minor. 1 As 

 soon as the imperial power came into the hands of the 

 Antonines, Greek literature and science revived in 

 some degree. There was a return to the past, which 

 was specially favourable to the latter studies. The 

 scientists were kept in practice by studying the great 

 works of their predecessors, and if they made no 

 original discoveries, they produced interesting com- 

 mentaries, or systematized the results already obtained. 

 Astronomy was brilliantly represented by Claudius 

 Ptolemy (date of birth uncertain, death probably 

 168 B.C.). Belonging to the Peripatetic School of 

 philosophy, Ptolemy defended the views of Aristotle on 

 the nature of matter and on gravitation ; he main- 

 tained, for example, that a bather does not feel any 

 pressure of the water above him, and that a bladder 

 1 25 Tannery, Science helttne, p. 5. 



