36 SCIENCE OF THE GREEKS. FT. i. 



be a discoverer yourself, you must not be content with 

 knowing what has been done, but must set to work as they 

 did, and observe and make experiments for yourself. 



Chief Works consulted. Draper's 'Intellectual Development in 

 Europe ; ' Lewis's ' Astronomy of the Ancients ; ' ' Encyclopaedia Bri- 

 tannica, ' art. ' Astronomy ; ' Herschel's ' Astronomy ; ' Baden Powell's 

 'History of Natural Philosophy;' Lardner's 'Cyclopaedia,' 1834; 

 Sprengel's ' Histoire de la Medecine,' 1815; Grant's 'History of 

 Physical Astronomy ; ' Lange's ' Geschichte des Materialismus ; ' Rees's 

 'Encyclopaedia ;' Whewell's ' History of Inductive Sciences.' 



