136 LABORATORY GUIDE IN BACTERIOLOGY 



3. Cultivation by Buchner's method, using fruit 

 jars. 



a) In a Mason fruit jar of ordinary type deposit 

 10 g. of pyrogallic acid. 



b) Smear vaselin around the mouth of the jar. 



c) Pour into the jar 100 c.c. of a i per cent solution 

 of NaOH. 



d) Deposit in the jar culture tubes previously in- 

 oculated. 



e) Fasten the cover of the jar, and incubate at 37° C. 

 for 48-72 hours. 



4. Cultivation in hydrogen gas. 



a) Inoculate all media from laboratory cultures. 



b) Fit up apparatus as shown in Fig. 33. 



c) Place cultiure tubes in a Novy jar (Fig. 33, a). 



d) Open the faucet (6) of the gas generator (c), con- 

 taining zinc and hydrochloric acid. The hydrogen gas 

 generated is purified by passing through two jars, one 

 of which contains concentrated sulphuric acid (d), the 

 other a 10 per cent solution of sodium hydrate (e). 

 Gradually the Novy jar is filled with hydrogen gas, 

 which can be ascertained by holding a culture tube 

 over the opening (/) and then over a burning match 

 or gas flame. As long as a detonation takes place the 

 hydrogen is mixed with atmospheric oxygen. When 

 the hydrogen in the Novy jar is pure, close it off by 

 turning the stoppers (g) and (6), and place the jar in 

 the incubator. The whole process occupies 10 or 15 

 minutes. 



5. A simple and effective method of anaerobic culti- 

 vation is as follows: Culture tubes, after inoculation, 

 are placed in a desiccation jar or any other jar with 



