PURE CULTURES IN PRACTICE. 



In order to be able to send the selected pure cultures in 

 a liquid condition to a distance, special forms of flasks were 

 devised by Hansen (Fig. 100) and by the author (Fig. 101). 

 The yeast can be sent a great distance in these flasks, and 

 there is no difficulty in safely transferring it from the flask 

 to the fermenting-cylinder of the propagating apparatus. 



In sending small quantities of pure cultures, in such a 

 manner that they may be safely and readily employed for 

 further cultivation, the small Hansen flasks are employed 



Fig. 100. Kig. 101. 



(p. 37). They are connected, in the flame, with the Pasteur 

 flask in which the pure culture has developed. A trace of the 

 yeast is transferred to the cotton-wool, and the flask is again 

 closed in the flame with the asbestos stopper, which is then 

 -coated with sealing-wax. When the culture is to be used, 

 the flask is again connected with a Pasteur flask containing 

 wort, and the yeast is rinsed into the latter. 



This process has made it possible to send large collections 



