ORIGIN OF LOWEST ORGANISMS. 99 



cisely similar conditions do nevertheless undergo 

 fermentation, this fresh fact is just as completely 

 adverse to the explanations and views of M. Pasteur, 

 as it is thoroughly harmonious with the doctrines of 

 Baron Liebig. The fluids which are capable of being 

 preserved generally not presenting a high degree of 

 fermentability do not undergo change, at ordinary 

 atmospheric pressure, after having been boiled, unless 

 they are brought into contact either with some pre- 

 existing living things or with some unaltered organic 

 particles from the atmosphere. Neither of these, how- 

 ever, can gain access to the fluid, in such a vessel ; 

 because all the air which enters, after the first inrush 

 into the still almost boiling fluid, has to pass, more or 

 less slowly, through the numerous flexures of the nar- 

 row neck of the flask and the two or three strata of 

 fluid which always remain therein. 



Some of the fluids which do not undergo chanee in 



o & 



these bent-neck vessels are, however, by no means 

 notable for possessing a low degree of fermentability. 

 This is the case, for instance, with infusions of turnip, 

 which, under other conditions, have been found to be 

 most prone to undergo fermentation. And, I have 

 found in several cases in which such an infusion 

 had been exposed in a bent-neck vessel, and had 

 remained unchanged for twelve or fourteen days (even 

 though subjected to a temperature of 85-95 R), that 

 if the neck of the flask were then broken shortly above 

 the bulb, the solution would still continue without 



H 2 



