6o THE ORIGIN OF LIFE 



phenomenon in time for every individual particle. 

 There are authorities like von Schron, of Naples, who 

 regard many stable bodies like crystals as forms of 

 elementary life. No doubt they have many qualities 

 in common with such bodies like bacteria, as are 

 admittedly living ; but for all that it seems to me 

 that it may be said they have everything in common 

 with microbes except the principle of vitality, and 

 may be regarded as the final products of such 

 elementary types of life as we have called radiobes. 

 They have everything but life. That perpetual 

 change of substance is absent, together with assimi- 

 lation on the one hand and decay on the other. 

 They thus appear to be nothing more than fossilised 

 remains of what may once have been living types. 



We therefore extend the rdle of life to all bodies 

 which are at once self-constructive and destructive ; 

 whose parts can come together and form systems 

 which are on the whole unstable, and thus separate 

 again into the constituent elements from which 

 they have been formed. If these bodies are like 

 little solar systems with their constituent particles 

 revolving round a centre, that central particle would 

 form the nucleus and the little system itself the 

 " cell." 



We therefore regard all bodies in which metabolism 

 occurs, whether by fermentation, catalysis, fluores- 

 cence, phosphorescence, or other types of luminosity 

 or radio-activity, as manifesting the most elementary 

 properties of vital activity — no doubt in its extreme 

 sense. 



