184 LABORATORY GUIDE IN BACTERIOLOGY 



The Bottcher Moist Chamber consists of a slide, a 

 cover slip, and a glass ring (see Fig. 35). The glass 

 ring is held on the slide by a mixture of rosin and castor 

 oil. A few drops of sterile water are placed in the 

 bottom to maintain moisture in the hollow of the ring. 

 The inverted cover slip with the hanging drop is held 

 in position by smearing vaselin around the top of the 

 glass ring. 



FIG. 35 



Bottcher Moist Chamber 



a. Slide ft. Glass ring c. Cover slip 



d. Hanging drop e. Sterile water 



EXERCISE 2 



Preparation of slides for microscopic study of molds, 

 also stained preparations (see p. 79). 



EXERCISE 3. STUDY OF MOLDS IN CHEESE 



1. Secure some Roquefort and some Camembert 

 cheese. 



2. Pick out with a looped needle some of the dark 

 spots in the Roquefort cheese and some of the mold on 

 the Camembert cheese. 



3. Make streaks of this material on wort agar plates. 



4. Isolate the molds and study as in Exercises i 

 and 2. 



EXERCISE 4. STUDY OF THE AMYLOLYTIC ACTION OF 

 MOLDS 



1. Prepare cultures of Aspergillus oryzae. 



2. Add some starch to liquid wort in a flask and 

 sterilize. 



