ON THE ROAD TO FAME 65 



that he ultimately succeeded; and this is the 

 way that he achieved his proof, thanks to his 

 practical qualities as an experimenter of ex- 

 treme caution who never left anything to 

 chance. 



After having half filled his globes with some 

 alterable liquid, such as an infusion of brewer's 

 yeast, Pasteur brought it to the boiling point, 

 and, when the steam had driven out all the air, 

 he quickly closed the point of the finely drawn- 

 out neck by means of a blow-pipe. The globes 

 thus prepared the liquid being contained in 

 an almost absolute vacuum were transported 

 to various different localities, and then opened 

 with infinite precautions: the fine point of the 

 neck was broken with pincers previously heated 

 in a flame, the air re-entered the globes, which 

 were immediately sealed again and placed in 

 ovens, where they were subjected to a tempera- 

 ture of 86 degrees Fahrenheit. The liquid be- 

 haved differently, according to the locality from 

 which the air had been obtained, the fermenta- 

 tion being very rapid if it had come from a 



