xv.] SPONTANEOUS GENERATION, 3G5 



the extent, I suppose I may say, of thousands of tons 

 every year, by a method which is a mere application 

 of Spallanzani's experiment. The matters to be pre- 

 served are well boiled in a tin case provided with a 

 small hole, and this hole is soldered up when all the 

 air in the case has been replaced by steam. By this 

 method they may be kept for years without putrefy- 

 ing, fermenting, or getting mouldy. Now, this is not 

 because oxygen is excluded, inasmuch as it is now 

 proved that free oxygen is not necessary for either fer- 

 mentation or putrefaction. It is not because the tins 

 are exhausted of air, for Vihinones and Bacteria live, 

 as Pasteur has shown, without air or free oxygen. It 

 is not because the boiled meats or vegetables are not 

 putrescible or fermentable, as those who have had the 

 misfortune to be in a ship supplied with unskilfully- 

 closed tins well know. What is it, therefore, but the 

 exclusion of germs ? I think that Abiogenists are 

 bound to answer this question before they ask us to 

 consider new experiments of precisely the same order. 

 And in the next place, if the results of the experi- 

 ments I refer to are really trustworthy, it by no means 

 follows that Abiogenesis has taken place. The resist- 

 ance of living matter to heat is known to vary within 

 considerable limits, and to depend, to some extent, 

 upon the chemical and physical qualities of the sur- 

 rounding medium. But, if, in the present state of sci- 

 ence, the alternative is offered us, either germs can 

 stand a greater heat than has been supposed, or the 

 molecules of dead matter, for no valid or intelligible 

 reason that is assigned, are able to rearrange them- 

 selves into living bodies, exactly such as can be de- 

 monstrated to be frequently produced in another way, 

 I cannot understand how choice can be, even for a 

 moment, doubtful. 



