CONTENTS 



Physical problems, p. 213 Attempts to explain the power of gravi- 

 tation, p. 214 The theory of Le Sage, p. 214 Speculations based 

 upon the hypothesis of the vortex atom, p. 216 Lord Kelvin's 

 estimate of the vortex theory, p. 217 Attempted explanation 

 of the affinity of atoms, p. 217 Solubility, as explained by 

 Ostwald and Mendeleef, p. 218 Professor Van 't Hoof's studies 

 of the space relations of atoms, p. 219 Life problems, p. 220 

 Question as to living forms on other worlds besides our own, p. 211 

 The question of the "spontaneous generation" of living proto- 

 plasm, p. 222 The question of the evolution from non-vital to vital 

 matter, p. 223 The possibility of producing organic matter from 

 inorganic in the laboratory, p. 224 Questions as to the structure of 

 the cell, p. 225 Van Beneden's discovery of the centrosome, p. 226 

 Some problems of anthropology, p. 227. 



CHAPTER IX 



RETROSPECT AND PROSPECT 



The scientific attitude of mind, p. 230 Natural versus supernatural, 

 p. 233 Inductive versus deductive reasoning, p. 235 Logical in- 

 duction versus hasty generalization, p. 239 The future of Darwin- 

 ism, p. 241. 



APPENDIX 243 



A LIST OF SOURCES 245 



INDEX 271 



