CONDITIONS TAVOUEING FEEMENTATIOF. 3 



ably sufficient to sterilize "urine when it was subsequently exposed 

 only to a " moteless air." Indeed, in regard to experiments made 

 witb " urine, mutton, beef, port, bay, turnip, tea, coffee, bops, had- 

 dock, sole, salmon, cod-fish, turbot, mullet, herring, eel, oyster, 

 whiting, liver, kidney, hare, rabbit, fowl, pheasant, grouse," amount- 

 ing in all to several hundreds, five minutes' boiling was always 

 found sufficient to produce complete sterilization. 



If, then, we omit from consideration those instances of " smoul- 

 dering fermentation"* in which, whilst the bulk of the fluid remains 

 clear, organisms are found mixed with sedimentary matter slowly 

 increasing in amount at the bottom of the vessel, and confine our- 

 selves solely to cases of well-marked fermentation characterized by 

 the supervention of unmistakable general turbidity due to the 

 multiplication of ferment-organisms, we shall have to deal with a 

 comparatively simple problem. There will in such cases be no 

 room for doubt as to whether or not the experimental fluids con- 

 tain organisms ; in the great majority of instances these will be 

 so numerous that even a tyro with the microscope could find 

 them. JSTeither will there be room for the supposition that the 

 organisms which are found are " dead and have been there 

 all the time." Dead organisms cannot by any stretch of fancy 

 be supposed to multiply so as to make a previously clear fluid 

 turbid. 



If, then, taking the fresh acid urine of a healthy person, and 

 boiling it so as to kill any organisms and germs which it may 

 contain, one is able, merely by subjecting this sterilized fluid to 

 certain physical and chemical influences, to cause it to ferment in 

 an unmistakable manner and swarm with living Bacteria, such a 

 procedure and its sequence could scarcely be otherwise regarded 

 than as a demonstrable proof of the truth of the physico-chemical 

 theory, and as an equally cogent disproof of M. Pasteur's exclu- 

 sive " germ theory " of fermentation. The same experiments 

 would coincidently afibrd clear evidence as to the occurrence of 

 so-caUed " spontaneous generation " f. 



* Proc. Eoy. Soc. vol. xxi. (1873) pp. 333 & 337. 



t This term will, I hope, after a time be discarded, because under it 

 two distinct processes have been included, which are liable to be improperly 

 confounded with one another. One process, which I designate by the word 

 archebiosis, includes the actual origination of living matter, its de novo forma- 

 tion; whilst the other, heterogenesis, signiQ-^Sdi, particular transformation of some 

 already existing living matter. 



1* 



