480 



INDEX 



Indestructibility of matter, taught 



by Democritus, 138 

 Index, Coppernicus' work placed on 



the, 171 



India, new route to, 79 

 Inferences, validity of scientific, 9 

 Infinitude, Lucretius' ideas on, 330 



of worlds, Democritus on, 135 

 Inhabitable worlds, enormous num- 

 ber of, 362 

 Inquisition, its capture of Bruno, 



179 

 endeavours to suppress works of 



Coppernicus and Kepler, 192 

 its frightful persecutions, 164 

 Instant 'ation , Great, quotation from 



Bacon's work, 216 

 Interaction of natural forces, a 



lecture by Helmholtz, 418 

 Interference, phenomena of, in light, 



346 

 Interregnum, accepted picture of, 



151 

 Inverse squares, law of, nearly 



reached by Kepler, 190 

 Invisible, astronomy of, 371 ^ 

 Ionian Greeks, their enterprise and 



culture, 131 

 Isis, priests of, 68 

 Isochronism of the pendulum, 



Galileo's discovery, 198 



JACOBI, on ideas of Anaxagoras, 123 



Joule, establishes the idea of con- 

 servation of energy, 416 



Julian Star, carries Caesar to the 

 skies, 270 



Jupiter, acceleration of motion, 300 



" Little world " of, presents an 



image of the solar system 



satellites of, obey Kepler's 



laws, 204 



moons of, discovered by Galileo, 

 201 



KANT, on moral sense of man, 39 

 criterion of knowledge, 146 

 founds the nebular hypothesis, 



405 



on cosmic structure, 387 

 on matter, 27 



Kapila, his philosophic views, 9 

 Kapteyn, explanation of appear- 

 ance of new star spectra, 381 

 Keeler, on spiral nebulae, 420 

 Kelvin, on age of the sun, 418 

 on dissipation of energy, 422 

 origin of life, 436 



Kepler, his life and ideas, 185 

 computes the distance of the 



sun, 228 



eulogy of Galileo, 209 

 his great discoveries ignored, 192 

 his rebuke to Rome, 205 

 on path of comets, 271 

 quoted on Galileo, title page 

 Kinetic theory of gases, 397 

 Kirchhoff, discovery of absorption 



spectra, 347 

 Kirmess, dance of the stars likened 



to a, 378 

 Knowledge, antiquity of, 9 



astronomical, synonym of certi- 

 tude, 377 



LACTANTIUS, on globular form of 



earth, 62 



derided by Coppernicus, 169 

 Lagrange, his co-operation with 



Laplace, 299 

 Lambert, acceleration of Saturn's 



motion, 300 



on structure of the universe, 387 

 Lange, history of materialism, 1 1 



on character of Gassendi, 221 

 Langley, illustration of the sun's 



heat, 417 

 parable on the end of the world, 



463 

 [Laplace, on early measures of the 



earth, 77 



eulogy of astronomy, 226 

 his life and work, 296 

 on Aristarchus, 89 

 on astronomy of the invisible, 372 

 sketch of the nebular hypothesis, 



410 

 Laughing Philosopher, Democritus 



called the, 142 

 Lavoisier, anticipations of his ideas 



by Democritus, 138 

 memoir on heat, 301 

 Law, idea of natural, 4 



scientific, Kepler a pioneer, 188 

 Layard, finds a convex lens in 



Nineveh, 200 

 Leaning Tower of Pisa used in 



Galileo's experiment, 198 

 Lebedeff, demonstrates pressure of 



light, 433 



Lecky, History of Rationalism, 1 1 

 Leibnitz, accusations against New- 

 ton, 263 

 idea of planets as extinct suns, 



402 

 invention of the calculus, 295 



