4-3 



PREFACE 



TIME was when the earth was supposed to be fixed 

 and have a flat surface, when the sun revolved 

 around the earth, and the moon as a luminary shed 

 forth its own light. Time was when dryads and 

 fauns dwelt in our forests, when fairies tripped upon 

 the greensward, and mermaids sang in the ocean. 

 Time flies, customs change, and knowledge pro- 

 gresses. We know now that the earth is not flat, 

 the moon is not a resplendent orb, that fairies do 

 not dance upon our lawns. Among the many 

 theories of the earth's origin none was so fiercely 

 fought as the nebular hypothesis, of man's origin 

 none caused such bitter antagonism as the evolu- 

 tionary theory, but both are now accepted by the 

 majority of men capable of considering their mean- 

 ing. One of the most popular ideas, one which 

 persists, and which our ever-increasing knowledge 

 has not changed, is that there are only two forms 

 of matter, inorganic and organic or dead and living 

 matter. It is supposed that there is no condition 

 between ; a thing is either living or it is dead, it 

 must be one or the other. In the gross this is true. 

 There is a mighty gulf between the living and the 

 dead. But how can we be sure that there is no inter- 

 mediate condition ? The question of Biogenesis 



v 



1818 



