50 THE GERM THEORY OF DISEASE. 



it was not without strong grounds in its favor. In Pasteur's 

 flasks the organisms were always transferred to fresh flasks, 

 together with a small quantity of the fermented fluid, which, 

 it was claimed, prepared the way for the development of the 

 bacteria. 



LISTER. 



Mr. Lister, at the London Congress, Vol. 2, page 371-2, 

 relates that he drew blood, with antiseptic precautions, from a 

 vein of an ox, into small, purified bottles, and allowed it to 

 clot. He then introduced various quantities of ordinary tap- 

 water (London hydrant water) into the different bottles. He 

 was surprised to find that even eight or ten drops failed to set 

 up putrefaction in the blood serum, while the one-hundredth 

 part of a drop of the same water was always sufficient to set 

 up putrefaction in milk. He experimented with the blood of 

 various animals with the same results. 



He found, however, that if the blood serum was diluted 

 with water purified by boiling, the smallest portion of tap- 

 water would then set up decomposition. He also found that 

 putrefying blood, very largely diluted with water, purified by 

 boiling, did not readily set up putrefaction, while the smallest 

 possible amount of the undiluted putrefying blood set up the 

 process at once. Speaking of the result, he says : " How it is 

 that diffusion of the bacteria renders them incapable of 

 developing in the serum, I do not profess to understand. It 

 may, perhaps, be, that when the bacteria are introduced 

 directly from putrid blood, the products of the putrid fer- 

 mentation adhering to them may induce, chemically, an altera- 

 tion in the normal quality of the serum, which, when thus 

 impaired, may prove amenable to the nutritive energies of the 

 micro-organisms] while, conversely, copious ablution with 

 water may remove from them the associated substances which 

 may thus act as their pioneers. The view might be otherwise 



