THE ORIGIN OF LIFE 



CHAPTER I 



INTRODUCTION. — THE NATURE OP THE PROBLEM 



Plan of the book — Eelationship of natural phenomena — The 

 continuity of vital processes — Historical — Aristotle, &c. — 

 Life as a series of molecular changes — The gradual scale 

 from the more complex to the simpler forms of molecular 

 aggregation — Luminosity and metabolism — Phosphores- 

 cence and the simpler forms of life — Physical evidence of 

 simple metabolism in fluorescent and in radio-active bodies 

 — Pfliiger's theory — Experiments with radium and bouiUon 

 — Borderland between mineral and vegetable kingdoms — 

 The dawn of life. 



The aspect of the question which it is the object of 

 this essay to expound in as familiar and yet 

 philosophic terms as the subject will itself admit of, 

 is primarily twofold. That twofold aspect is that 

 of actual knowledge and of speculation. For in its 

 first origin as well as in its last end, life remains 

 and doubtless for long ages, if not for ever, will 

 remain a mystery to the intelligence of human 

 beings. Between these two limits, however, there 

 is much known and to be known. And the two 

 means of attack may work together although 



B 



