418 



MICRO-ORGANISMS AND FERMENTATION. 



the cylinder. At the bottom is the cock Q, which is connected 

 with the pipe b by cock T. Both the bent tubes dip into 

 the vessel R, which is filled with water. 



The wort is introduced into the lower cylinder, where it is 

 treated in the ordinary manner. The pure culture is intro- 

 duced into the upper cylinder, and is then washed down 



into the lower cylinder by 

 means of a little wort, 

 which is forced from B into 

 A, and then back again 

 into B. When a vigorous 

 multiplication of the yeast 

 has set in, the liquid is 

 stirred up, and a portion 

 forced into A ; this is to be 

 used to start the next fer- 

 mentation. The cylinder 

 B thus serves alternately 

 as fermenting- and wort- 

 cylinder. 



A comprehensive intro- 

 duction to the method of 

 dealing with the apparatus 

 used in the laboratory for 

 the preparation of pure 

 cultures (moist chambers 

 and flasks) is to be found, 

 along with the mode of 

 operating the two types of 

 propagating apparatus, in 

 a small hand-book of the 

 author's, entitled Practi- 



Fig. 99. Yeast-propagatinp: apparatus devised by Cal Management of Pure 

 Bergh and Jorgensen. -* 7 , T j , nnn j- 



Yeast, London, 1903. Modi- 

 fications of both forms of propagating apparatus have been 

 described by Brown and Morris, Elion, Thausing, Van Laer, 

 Pohl and Bauer, Wichmann, Fernbach, Jacquemin, and others. 

 P. Lindner and Marx have constructed a somewhat different 

 apparatus. 



