47 8 



INDEX 



Faust, quotation from, 38 



Ferdinand and Isabella, court of, its 

 enlightenment, 63 



Fernel, his measure of the earth, 164 



Fez, Saracen capital, 154 



Figure of the earth, established by 

 Newton, 261 



Finality, impossible in human know- 

 ledge, 445 



Fire, discovery of, 50 



First magnitude stars, average 

 distance, 360 



FitzGerald, his translations of Omar, 



155 



Fixity in events, difficulty of re- 

 cognising, 4 



Fleming, Mrs., discovery of new 

 stars, 379 



Fluxions, invented by Newton, 255 



Fontenelle, on the plurality of 

 worlds, 233 



Fools, Galileo on number of, 199 



Foot, unit of length, 54 



Force, clarifying conceptions of, 242 

 persistence of, Spencer's phrase, 



415 



Forefathers, savagery of our, 14 

 Foster, Sir Michael, quotation of, 



144 

 Foucault, on wave theory of light, 



346 



Fourth dimension, is improbable, 9 

 Foxes, methods of reasoning in, 9 

 Fraunhofer, perfects the helio- 



meter, 333 



maps spectrum lines, 346 

 Frederick the Great, invites French- 

 men to Berlin, 299 

 Kant's work dedicated to, 406 

 Freedom of the will, its denial by 



Democritus, 141 

 Fresnel, wave theory of light, 346 



GALILEO, Kepler's tribute to, title 



page 



an early Coppermcan, 177 

 and Kepler, neither could make 



use of each other's work, 207 

 correspondence with Kepler, 199 

 estimate of his work, 208 

 his abjuration, his life and ideas, 



197 



on distribution of the stars, 281 

 on nature's horror of a vacuum, 



240 



on parallax of sun, 95 

 to Newton, amazing change of 



ideas from, 326 



Galle, discovers Neptune, 312 

 Gascoigne, effect of his inventions, 



95 

 invention of micrometer threads, 



244 



Gases, spectrum of, 346 

 kinetic theory of, 397 

 Gassendi, his life and ideas, 219 

 Gauss, his method of least squares, 



308 



General Natural History of the 

 Heavens, a work by Kant, 406 

 Generation, spontaneous, no evi- 

 dence for, 436 

 Genius, innateness of, 185 

 Geometers, their modes of reason- 

 ing, 104 

 Geometry, antiquity of, 9 



analytic, developed by Descartes, 



217 



rise of, 56 

 Gerber, on rate of propagation of 



gravitation, 453 

 Gibbon, ^on Omar Khayyam's 



calendar, 155 

 Gilbert of Colchester, advocate of 



Coppernican theory, 1 76 

 compared with Lord Bacon, 215 

 his ideas on attraction, 190 

 Gill, Sir David, on distance of 



Canopus, 360 

 Gravitation, first ideas of, 23 



influence on fauna of planets, 365 

 investigation of by Royal Society, 



247 



Kant on universality of, 407 

 Kepler on, 188 



possible rate of propagation, 453 

 relative strength of, 445 

 Seeltger on difficulties in law of, 



447 



the riddle of Newton on diffi- 

 culties of conceiving, 449 



Gravity, Coppernicus on, 170 



Greek science, just misses modern 

 world conception, 128 



Greeks, the legacy of, 145 



Gregory the Great, mentioned, 152 



Grindstone theory of stellar ar- 

 rangement, 387 



Guericke, Otto von, invents the air- 

 pump, 241 



Gunpowder, introduction of, 158 



HALL, Maxwell, his system of the 



stars, 396 

 Halley, on new method of fixing 



sun's distance, 231 



