VITALITY OF PUTEEFACTIVE ORGA.NISMS. 205 



will be the first to give way. A germ, moreover, brought 

 close to the death-point in a neutral or in an alkaline in- 

 fusion may revive, while in an acid one it may perish — 

 just as proper nutriment may rescue a dying man, while 

 improper nutriment would fail to do so. These elemen- 

 tary considerations, founded on the demonstrable fact 

 that Bacteria-gevms are more fully vivified and better 

 nourished in neutral infusions than in acid ones, suffice, 

 I think, to explain the observed diiference of action. 

 At all events, these are the thoughts which have be- 

 come rooted in my mind, through long observation and 

 long pondering of this question.^ 



§ 21. Remarl's on the Germs of Bacteria as 

 distinguished from Bacteria themselves. 



The failiu*e to distinguish between these stubborn 

 germs and the soft and sensitive organisms which 

 spring from them has been a source of error in writings 

 on Biogenesis. In his able and important paper, 

 *0n the Origin and Distribution of Bacteria in Water, 

 and the circumstances which determine their exist- 

 ence in the Tissues and Liquids of the Living Body,' 

 Dr. Burdon Sanderson, for example, has described ex- 

 periments from which, in my opinion, very incorrect 

 conclusions have been drawn. He exposed to the com- 

 mon air vessels containing Pasteur's solution, which 

 when inoculated with fully developed Bacteria enables 

 them freely and copiously to increase and multiply; 



' From their deportment in boiling-, I should infer that the air 

 dissolved in an alkaline liquid is in a different physical condition 

 from that dissolved in an acid liquid ; and to this, in some measure, 

 the difference of nutritive power may be due. I have been unable 

 to find any experiments on the comparative absorption of air by 

 acid and neutral liquids. The subject is, I think, well deserving of 

 attention. 



