18 THE ORIGIN OF LIFE 



looking to the organic nature of his media, which 

 would probably be sufficient to destroy their 

 " germinality." My objects are, of course, quite 

 different. What I try to do is, while heating the 

 fluids and vessels sufficiently to kill all pre-existing 

 living things, not unnecessarily to degrade or 

 break up the colloidal compounds contained in the 

 solutions (though such as exist in my saline solu- 

 tions seem to resist much higher degrees of heat 

 than those that are to be found in organic solu- 

 tions) ; and then, after a time, to examine very 

 carefully the minute and unobtrusive deposits that 

 are to be found in the vessels. For in these high- 

 temperature experiments there is never the pro- 

 duction of general turbidity. The organisms are 

 always comparatively scarce and to be found only 

 at the bottom of the vessel. 1 



Another important direction, however, in which 

 my work appears to come into conflict with that 



1 In regard to the media of the bacteriologist there are two 

 points which have perhaps hitherto been insufficiently considered 

 in this relation: (a) That suitable uninoculated media which 

 have been kept for some time, and had not been too much 

 superheated, have never had their minute and unobtrusive de- 

 posits scrutinised; and (6) that the changes set up by inocula- 

 tion would not be interfered with by any such processes as have 

 been referred to above. The inoculation changes would begin 

 to occur at once, and would probably render abortive any other 

 much slower processes that might otherwise have occurred. 



