334 



LOUIS PASTEUR 



in ?. bath of chloride of calcium in a large cylindrical white 

 iron pot set over a flame. The exit tube of the flask was 

 plunged in a test tube of Bohemian glass three-quarters 

 full of distilled water, and also heated by a flame. We 

 boiled the liquids in the flask and test-tube for a suf- 

 ficient time to expel all the air contained in them. We 



FIG. 9 



then withdrew the heat from under the test-tube, and im- 

 mediately afterwards covered the water which it contained 

 with a layer of oil and then permitted the whole apparatus 

 to cool down. 



Next day 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 permitted the flask to remain in this state for a fort- 

 night. It might have remained there for a century without 

 ever manifesting the least sign of fermentation, the fer- 

 mentation of the tartrate being a consequence of life, 

 and life after 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 



