CONTENTS 



Haeckel's laboratory, p. 160 His method of working, p. 161 

 His methods of teaching, p. 164 The import of the study of zool- 

 ogy, p. 166 Its bearing upon evolution, p. 168 The present 

 status of Haeckel's genealogical tree regarding the ancestry of man, 

 p. 171 Dubois's discovery of the skull of the ape-man of Java, p. 

 173 Its close resemblance to the skull of the ape, p. 173 Man's 

 line of descent clearly traced by Haeckel, p. 175 The "missing 

 link" no longer missing, p. 176. 



CHAPTER VII 



SOME MEDICAL LABORATORIES AND MEDICAL PROBLEMS 



The Boulevard Pasteur, p. 179 The Pasteur Institute, p. 180 

 The tomb of Pasteur within the walls, p. 181 Aims and objects of 

 the Pasteur Institute, p. 182 Antirabic treatment given, p. 183 

 Methods of teaching in the institute, p. 185 The director of 

 the institute and his associates, p. 185 The Virchow Institute of 

 Pathology, p. 186 Studies of the causes of diseases, p. 187 Or- 

 ganic action and studies of cellular activities, p. 188 The discov- 

 eries of Rudolph Virchow. p. 188 His work in pathology, p. 189 

 Character of the man, his ways of living and working, p. 189 His 

 methods of lecturing and teaching, p. 191 The Berlin Institute of 

 Hygiene, p. 193 Work of Professor Koch as carried on in the in- 

 stitute, p. 194 Work of his successors in the institute, p. 195 

 Investigations in hygiene, p. 196 Investigations of the functions of 

 the human body in their relations to everyday environment, p. 

 197 The Museum of Hygiene, p. 198 Studies in methods of con- 

 structing sewerage systems in large cities, p. 199 Studies in prob- 

 lems of ventilation, p. 200. 



CHAPTER VIII 



SOME UNSOLVED SCIENTIFIC PROBLEMS 



The ever-shifting ground of scientific progress, p. 203 Solar and 

 telluric problems, p. 205 Mayer's explanation of the continued 

 heat of the sun, p. 206 Helmholtz's suggestion as to the explana- 

 tion, p. 207 The estimate of the heat-giving life of the sun by Lord 

 Kelvin and Professor Tait, p. 208 Lockyer's suggestion that the 

 chemical combination of elements might account for the sun's 

 heat, p. 209 Computations as to the age of the earth's crust, p. 

 210 Lord Kelvin's computation of the rigidity of the telluric 

 structure, p. 211 Estimates of the future life of the earth, p. 212 



vi 



