286 STUDIES ON FERMKNTATION. 



Next da}' we applied a finger to the open extremity of the 

 exit-tube, which we then plunged in a vessel of mercury. In 

 this particular experiment which we are describing, we per- 

 mitted the flask to remain in this state for a fortnight. It 

 might have remained for a century without ever manifesting 

 the least sign of fermentation, the fermentation of the tartrate 

 being a consequence of life, and life after the boiling no longer 

 existed in the flask. When it was evident that the contents of 

 the flask were perfectly inert, we impregnated them rapidly, as 

 follows : — All the liquid contained in the exit-tube was removed 

 by means of a fine caoutchouc tube, and replaced by about 1 c.c. 

 (about 17 minims) of liquid and deposit from another flask, 

 similar to the one we have described, but which had been fer- 

 menting spontaneously for twelve days ; we lost no time in 

 refilling completely the exit-tube with water which had been 

 first boiled and then cooled down in carbonic acid gas. This 

 operation lasted only a few minutes. The exit-tube was again 

 plunged under mercury. Subsequently the tube was not 

 moved from under the mercury, and as it formed part of the 

 flask, and there was neither cork nor india-rubber, any intro- 

 duction of air was consequently impossible. The small quantity 

 of air introduced during the impregnation was insignificant, and 

 it might even be shown that it injured rather than assisted the 

 growth of the organisms, inasmuch as these consisted of adult 

 individuals which had lived without air and might be liable to 

 be damaged or even destroyed by it. Be this as it may, in a 

 subsequent experiment we shall find the possibility removed of 

 any aeration taking place in this way, however infinitesimal, so 

 that no doubt may linger on this subject. 



The following days the organisms multiplied, the deposit of 

 tartrate gradually disappeared, and a sensible ferment action 

 was manifest on the surface, and throughout the bulk of the 

 liquid. The deposit seemed lifted up in places, and was covered 

 with a layer of a dark-grey colour, puffed up, and having an 

 organic and gelatinous appearance. For several days, in spite 

 of this action in the deposit, we detected no disengagement c 



