STUDIES ON FERMENTATION. 191 



submitting it to examination, we could find nothing but rami- 

 fied gi'oups in fine condition, witbout a single elongated cell, 

 indeed, it would have been impossible to find a more beautiful 

 specimen of " higli " yeast, or one of a more decided character. 

 It would seem, therefore, that " high " yeast cannot, under any 

 circumstances, assume the form and character of the ferment 

 mccharomycei<. padorianus, or of other known ferments. We are 

 justified, therefore, in regarding it as a distinct species of 

 ferment, an opinion which is supported by other circumstances. 



1. In equal quantities of saccharine wort a considerably 

 greater growth of " high " yeast is obtained than of other 

 3-easts. We need no very rigorous proofs to convince our- 

 selves of this fact : for by simply causing equal volumes of 

 the same wort to ferment, the one being pitched with saccha- 

 romyces padorianus, for example, the other with " high " yeast, we 

 shall obtain a perceptibly greater volume of " high " yeast than 

 of the other, in certain cases even five or six times as much. 



2. " High " yeast is of a tougher texture than the others, 

 separating, when the fermented liquor and its deposit is shaken 

 up, into lumps which refuse to disappear ; whereas saccharo- 

 inyccs pastorianus difiuses through the whole liquid with the 

 greatest ease. 



3. " High " yeast produces a special beer, with a peculiar 

 flavour, well known to consumers, but little esteemed at the 

 present day. Hence the gradual displacement of breweries 

 worked on the old " high " i'ermentation system by others 

 in which " low " yeast (of which more anon) alone is employed. 



4. Lastly, one characteristic of " high " yeast, which it 

 shares in common with some other ferments, although not 

 with all, and which, from a practical point of view, deserves 

 special mention, is that as fermentation proceeds the yeast 

 rises to the surface of the liquid. Whilst the process of the 

 manufacture of beer by this ferment is going on, the yeast 

 is seen to work out of the bung-holes, flowing over in con- 

 siderable quantit3\ The ferment named after the author, as 

 well as " low ■" yeast, does not possess this property : it remains 



