T 



FOREWORD 



"^HE discoveries in astronomy during the last decade have not only 

 widened the boundaries of our own universe but have revealed the 

 existence of universes far beyond our own. These discoveries prove 

 that in our own and the outer universes exactly the same physical and chem- 

 ical principles prevail, namely, gravitation, heat, hght, the genesis of new 

 compounds, development from nebulous and active phases mto dark and 

 inert phases of death. 



Marvelous as are these recent discoveries in astronomy, they are becom- 

 ing comprehensible because of the uniformity of the laws and principles 

 revealed to man through centuries of research. In brief, physics, astronomy 

 and chemistry are ahke coming within the field of exact science capable of 

 measurement, calculation, prediction and prophecy. 



What a contrast is presented in the biological sciences, ancient and 

 modern ! With a wide circle of astronomic friends and with the most intense 

 admiration for the achievements of astronomy and pure mathematics, I 

 yet believe that their problems are not nearly so difficult or so baffling 

 as our problem. In anatomy, in physiology, in pathology, in heredity we 

 have not yet reached even the threshold of exactitude. With increasing 

 energy, refinement and ingenuity, we know all the organs revealed in com- 

 parative and human anatomy, in both their grosser and their finer structure. 

 We know also the history of the rise of many of these organs in the course of 

 past time and what their functions and relations are, but there is always the 

 Great Beyond of the unknown, and perhaps unknowable, which is summed 

 up in the word life. 



Of all incomprehensible things in the universe Man stands in the front 

 rank, and of all incomprehensible things in Man the supreme difficulty centers 

 in human intelligence, human memory, human aspirations, human powers of 



