4.

Further, Hipparchus and many others are of opinion that the parallel of latitude of the Dnieper does not differ from that of Britain; since that of Byzantium and Marseilles are the same. The degree of shadow from the gnomon which Pytheas states he observed at Marseilles being exactly equal to that which Hipparchus says he found at Byzantium; the periods of observation being in both cases similar.452 Now from Marseilles to the centre of Britain is not more than 5000 stadia; and if from the centre of Britain we advance north not more than 4000 stadia, we arrive at a temperature in which it is scarcely possible to exist. Such indeed is that of Ierne.453 Consequently the far region in which Eratosthenes places Thule must be totally uninhabitable. By what guess-work he arrived at the conclusion that between the latitude of Thule and the Dnieper there was a distance of 11,500 stadia I am unable to divine.