en. v. PTOLEMY, STRABO, AND PUNY. 33 



whether you moved round the ball, or the ball round you, 

 in our experiment on page 1 9 ; and Ptolemy's explanations 

 were apparently so near the truth that astronomers were 

 satisfied with them for 1400 years, till Copernicus discovered 

 the real movements. 



Ptolemy was a geographer as well as an astronomer ; 

 he wrote a book on geography which was used in all the 

 schools of learning for nearly fourteen hundred years. He 

 drew maps of all the known parts of the world, and laid 

 down on them lines of latitude and longitude, which he 

 calculated by the rules Eratosthenes had discovered. In 

 his geography he describes the countries from the Canary 

 Islands on the west to India and China on the east, and 

 from Norway to the south of Egypt. He describes our 

 island under the name of Albion, or Britain, and traces out 

 many of the coast-lines and rivers. He also gives the names 

 of the various towns, with their latitude and longitude. 



Strabo and Pliny.' Between the beginning of our era 

 and the time of Ptolemy there lived two remarkable men 

 who require a passing mention. The first of these was a 

 famous traveller named Strabo, who wrote a great deal on 

 geography. He was born at Amasia, in Cappadocia, and 

 was probably living when Christ was born. Strabo in his 

 book describes the countries which he visited and read 

 about. He also studied earthquakes and volcanoes, and 

 pointed out that when the hot vapour and lava hidden in 

 the crust of our earth cannot escape, they cause earth- 

 quakes, but that when they find their way out through a 

 volcano, like Etna, the country is not so often disturbed 

 and shaken. The second of these men, Pliny, the famous 

 naturalist, was born A.D. 23, and died in the year 79 in a 

 rash attempt to approach Vesuvius during the celebrated 

 eruption which overwhelmed Herculaneum and Pompeii. 



