PURE YEAST CULTURE. 247 



After my visit to England, experiments were commenced 

 in some of the breweries there, and new advocates of my 

 system came forward, and amongst them Hagen-Schow, Dr. 

 Sykes and Dr. Stanley Smith. For some years several brew- 

 eries in different parts of England have had regular supplies 

 of pure cultivated high yeast from A. Jorgensen's laboratory 

 at Copenhagen. I conclude from this that these must have 

 given satisfactory results, as otherwise the supplies would 

 scarcely have been continually renewed. Recently a com- 

 pany, called The British Pure Yeast Company, has been 

 started at Burton-on-Trent. The technical director is Pro- 

 fessor Van Laer, who is also director of the Belgian company 

 mentioned above ; the object of the company is to supply 

 pure cultivated yeast to the breweries of Great Britain. 



As far as can be seen from statements emanating from 

 the Burton company, I must assume that the yeast which 

 it supplies is a composite one, consisting of several species. 

 In his paper in the ' Transactions of the Institute of Brewing,' 

 1894,' Van Laer postulates that the yeast in English high- 

 fermentation breweries must necessarily consist of several 

 species, as, according to his view, a secondary fermentation 

 will not otherwise be obtained. In one of my treatises, 

 published in 1883, I showed that on inoculating beer with 

 a species of yeast which under ordinary circumstances causes 

 beer sickness, it is possible under certain conditions to obtain 

 a good effect. Van Laer has now adopted this idea, and 

 carried it out further than is admissible, in that he assumes 

 that beer fermented with a single species is less resistive to 

 infection than beer fermented with several species. Every 

 experienced investigator knows, however, that such generalis- 

 ations are never correct. If a mixed yeast is to be safe, the 

 ratio between the different species present must remain con- 

 stant during the fermentation in the brewery. It is at once 

 evident that this is inconceivable. 



When Horace T. Brown and Gordon Salamon drew 



