STUDIES ON FERMENTATION. 



339 



The cork and glass tube used for this purpose had previously 

 been treated with boiling water. 



AVhen the wort had cooled down in the flask and matters 

 were arranged as represented in Fig. 75, I raised the two- 

 necked flask so as to cause a little of the liquid and yeast to flow 

 into the wort. Thereupon fermentation was set up, and the 

 resulting carbonic acid gas made its escape by the drawn-out 

 end of the doubled-necked flask. The entire arrano-ement with 



Fig. 75. 



its supporting stand remained in this connection for eighteen 

 months, sometimes on a stove, sometimes in the laboratory, 

 exposed to all the variations of external temperature. At the 

 end of that time I tasted the beer in the flask ; it was perfectly 

 sound, and the ferment, submitted to the microscope, showed not 

 the slightest trace of any foreign ferments : and, doubtless, the 



z 2 



