BOOK II. Lxxv. 185-LXXIX. 188 



night. Alexander's guide Onesicritus wrote that 

 this constellation is not visible at the places in India 

 where there are no shadows, and that these places 

 are called Shadeless, and no reckoning is kept of 

 the hours there. LXXVI. But according to Eratos- 

 thenes in the whole " of Cave-dweller Country on 

 90 days once a year shadows fall the wrong way.* 



LXXVII. Thus it comes about that owing to the Daylight 

 varied lengthening of dayhght the longest day ]Zitu£^ 

 covers 12| equinoctial hours at Meroe, but 14 hours 

 at Alexandria, 15 in Italy, and 17 in Britain, where the 

 hffht niofhts in summer substantiate what theory 

 compels us to beheve, that, as on summer days * 

 the sun approaches nearer to the top of the world, 

 owing to a narrow circuit of Hght the underlying 

 parts of the earth have continuous days for 6 months 

 at a time, and continuous nights when the sun has 

 withdrawn in the opposite direction towards winter. 

 Pytheas of Marseilles writes that this occurs in 

 the island of Thule,'^ 6 days' voyage N. from Britain, 

 and some declare it also to occur in the Isle of 

 Anglesea, which is about 200 miles * from the British 

 town of Colchester. 



LXXVIII. This theory of shadows and the Thefirst 

 science called gnomonics was discovered by Anaxi- ■'""''"* • 

 menes of Miletus, the pupil of Anaximander of whom 

 we have spoken ; he first exhibited at Sparta the 

 time-piece they call ' Hunt-the-Shadow.' 



LXXIX. The actual period of a day has been Day 

 differently kept by different people : the Babylonians \Zk(med. 

 count the period between two sumises, the Athenians 



"* Now thought to be N.W. Norway. 



' I.e. by the Roman Road from Colchcster, the capital of the 

 pioviuce, by Graiitchester or Cheatertou to Chester. 



