- INTRODUCTION 33 



dealt with by the combined researches of chemists 

 and physicists. We may, however, profitably in- 

 quire whether solutions can be devised which, after 

 thorough sterilisation and continued protection 

 from outside contamination, will, as a result of 

 natural tendencies, and after weeks or months 

 of exposure to particular conditions, lead to the 

 appearance therein of living units. If so, many 

 old and widely accepted theories would have to 

 give place to altogether new views having most 

 important bearings upon many departments of 

 natural knowledge. 



