FERMENTATION. 255 



minded of that seed which fell into good ground, and 

 brought forth fruit, some thirty fold, some sixty fold, 

 some an hundred fold? On examination, this notion 

 of organic growth turns out to be more than a mere 

 surmise. In the year 1680, when the microscope was 

 still in its infancy, Leeuwenhoek turned the instru- 

 ment upon this substance, and found it composed of 

 minute globules suspended in a liquid. Thus knowl- 

 edge rested until 1835, when Cagniard de la Tour in 

 France, and Schwann in Germany, independently, but 

 animated by a common thought, turned microscopes 

 of improved definition and heightened powers upon 

 yeast, and found it budding and sprouting before their 

 eyes. The augmentation of the yeast alluded to above 

 was thus proved to arise from the growth of a minute 

 plant now called Torula (or Saccharomyces) Cerevisice. 

 Spontaneous generation is therefore out of the ques- 

 tion. The brewer deliberately sows the yeast-plant, 

 which grows and multiplies in the wort as its proper 

 soil. This discovery marks an epoch in the history of 

 fermentation. 



But where did the brewer find his yeast? The reply 

 to this question is similar to that which must be given 

 if it were asked where the brewer found his barley. He 

 has received the seeds of both of them from preceding 

 generations. Could we connect without solution of con- 

 tinuity the present with the past, we should probably 

 be able to trace back the yeast employed by my friend 

 Sir Fowell Buxton to-day to that employed by some 

 Egyptian brewer two thousand years ago. But you may 

 urge that there must have been a time when the first 

 yeast-cell was generated. Granted exactly as there 

 was a time when the first barley-corn was generated. 

 Let not the delusion lay hold of you that a living thing 

 is easily generated because it is small. Both the yeast- 



