BIOGRAPHICAL INDEX 



several political positions, Was Minister of 

 Agriculture and Commerce, 1840-1851. 



Edison, Thomas A., vi, 228; vii, 182. Born at 

 Milan, Ohio, Feb. n, 1847. Inventor of the 

 phonograph, the incandescent lamp and light 

 system, a system of wireless telegraphy, and 

 more than seven hundred other inventions, or 

 improvements on mechanical devices. 



Empedocles, i, 1 14. Born at Agrigentum, Sic- 

 ily, cir. 490 B.C.; died cir. 430 B.C. Greek 

 philosopher and physician. In his philosophical 

 teachings he assumed four elements, earth, air, 

 fire, and water, which existed together immov- 

 able in the perfect primitive world by means of 

 an uniting cause "Friendship," until the external 

 separating cause "Strife" entered into the world 

 and acting on the elements gave rise to all indi- 

 vidual and contrary phenomena. 



Erasistratus, i, 194. Born at Julis, Ceos, cir. 

 330 B.C. Greek physician. Became body physi- 

 cian at Court of King Selectus Nicator of Syria. 

 Went to live in Pamos and gave himself up to 

 study of anatomy. He was the first to perceive 

 the difference between the sensory and motor 

 nerves, and traced both to the brain. He seemed 

 to have some idea of the circulation of the 

 blood, and of the functions of the veins and 

 arteries. 



Eratosthenes, i, 225. Born at Cyrene, cir. 275 

 B.C.; died at Alexandria, 195 B.C. Greek as- 

 tronomer and geometer, pupil of Lysanias and 

 Callimachus. Went to Athens. 240, succeeded 

 Callimachus as head of the Alexandrian Library. 

 Became blind and voluntarily starved himself 

 to death. Attempted to measure the obliquity 



