THE BEGINNINGS OF LIFE, 429 



resultants of a more complex set of antecedent condi- 

 tions. Chance finds no recognized place where law, 

 or uniformity of result, is eternal. New doctrines 

 must, therefore, before their period of general ac- 

 ceptance, be shown to rest upon phenomena that are 

 easily obtainable. Facts which can be attested by all 

 are not to be gainsayed by any amount of theorizing, 

 or mere affirmation of opposite c mental convictions.' 



The uniformity in the properties of living matter, 

 as it exists in the simplest living things, is recognized 

 by all biologists. All minute, naked, living organisms 

 with which experiment has been made, have been killed 

 by being immersed for a few minutes in water raised 

 to the temperature of I4OF; so that, judging from this 

 known uniformity, there is very good reason for believing 

 that such an amount of heat would prove destructive 

 to all similar,, minute, naked portions of living matter. 

 With regard to the higher temperature of 2i2F, how- 

 ever, there is the most unanimous agreement (amongst 

 all those who are best entitled to speak upon .the 

 subject) as to the fact that such an amount of heat is 

 destructive to all the lower forms of life which' are to 

 be met with in infusions. 



On the other hand, the labours of very many experi- 

 menters have now placed it beyond all question of 

 doubt or cavil, that living Bacteria, Tortile, and other 

 low forms of life, will make their appearance and 

 multiply within hermetically-sealed flasks (containing 

 organic infusions), which had been previously heated to 



