22 THE BEGINNINGS OF LIFE. 



Turning now, however, to another aspect of the 

 question, and accepting the fact that specks of living 

 matter, which speedily develop into the simplest 

 organic forms, are capable of arising de novo.^ we are 

 at once met with the query — Out of what materials has 

 this living matter been developed, and what were the 

 steps of the process? In my experiments I have 

 employed, (i) Simple infusions containing organic 

 matter, (2) Saline solutions to which, in addition to 

 any unknown organic impurities, a fragment of organic 

 matter had been purposely added j and also (3) Saline 

 solutions to which nothing was added, but which may 

 have contained accidental organic impurities. 



So far as the organic infusions are concerned, we 

 know that these contain complex colloidal molecules in 

 solution, which, though altered and more or less degraded 

 in quality by the influence of the high temperatures, 

 have probably still retained some of their characteristic 

 properties. So that, after a time, under the continued 

 influence of heat, light, and other agencies, new com- 

 binations may have been brought about amongst these 

 mobile compounds, till continuous changes- of a fer- 

 mentative character were initiated^ which resulted in the 

 coincident production of specks of living matter. These 

 are supposed to be formed by the occurrence of new 

 combinations amongst the colloidal molecules them- 

 selves, of a kind similar to those which must occur 

 when the elements of ammonic cyanate assume the 

 more complex arrangement which converts them into 



