216 MICRO-ORGANISMS AND FERMENTATION. 



this reform into science and practice ; other treatises, which 

 discuss the subject, but which show a misunderstanding of 

 the separate links or of the kernel of the system ; and, 

 finally, a number of valuable investigations, the object of 

 which is to throw light on the system from various sides 

 and thus to facilitate a true conception and the practical 

 application of the system. 



It would lead us too far to discuss these different sides 

 of the literature. In concluding this description, I will 

 confine myself to a few quotations from the highest 

 authorities who have thrown light on the subject from 

 various points of view, and have merited the greatest 

 praise in helping the extension of the system in different 

 countries. 



Professor Lintner, sen., gives the following review of 

 the situation in 1885 1 : 



"Now that different breweries have employed pure 

 cultivations of the Carlsberg yeasts, and that the Scientific 

 Station at Munich has also introduced pure cultivations of 

 Munich yeasts into various breweries, the results obtained 

 may be summarised as follows : 



"1. By contamination with so-called wild yeasts, a 

 brewery-yeast, normal in other respects, may grad- 

 ually become incapable of producing a beer of 

 good flavour and with good keeping properties. 



" 2. A contamination of this kind can occur through 

 wild yeasts present in atmospheric dust during 

 summer and autumn, or the wild yeast may be 

 introduced with the pitching-yeast or with cask 

 sediment. 



" 3. By means of Hansen's methods of analysis and pure 

 cultivation, it is possible to isolate from a contami- 

 nated yeast, the desired brewery-yeast in a good and 

 pure condition. 



1 Zeitsclirift f . d. ges. Brauw., 1885, p. 399. 



