VITALITY OF PUTKEFACTIVE ORGANISMS. 



185 



Experiments intended to determine the limit of 

 resistance of cucumber-infusion were made on the 24th 

 of February. Nine pipette-bulbs were then charged, 

 plugged, hermetically sealed, and subjected to the boil- 

 ing temperature for the following times : — 



15 minutes. 



30 



45 



60 

 120 

 180 

 240 

 300 

 360 



After boiling and cooling they had as usual their 

 ends broken off by a file. The result here was that at 

 the 5th bulb, which corresponded to a boiling for two 

 hours, the life-development suddenly ceased. All the 

 tubes boiled from three to six hours inclusive were com- 

 pletely sterilized. 



The infusion in this case had been diluted by an 

 accident, so that its specific gravity was not much above 

 that of distilled water. On the 28th of February, 

 therefore, a fresh infusion having a specific gravity of 

 1006 was prepared, and introduced into a series of 

 bulbs exactly as in last experiment. The bulbs were 

 exposed to the boiling temperature for the following 

 times : — 



