14 LABORATORY BACTERIOLOGY 
EXERCISE V 
INOCULATING TUBES OF BOUILLON, AGAR, AND 
GELATIN 
19. Work for this exercise. See that the media made in 
former exercises have been properly sterilized. Inoculate one 
tube of bouillon, two (one inclined, the other not) of agar, and 
one of gelatin from a culture of Bacillus coli ~guramemes, which 
will be furnished. 
Wipe the slides. Transfer the cover glasses from the clean- 
ing mixture to water and then to alcohol. Seal the agar slant 
and gelatin tubes. 
Read the chapters in one or more text-books on inoculating 
media or making tube cultures. ¥ 
20. Inoculating bouillon. In making this culture, carefully V, 
remove the plug from the tube of bouillon by first twisting it’, 
around to detach any adhesions and then by pulling it straight | 
out. Pass the open end of the tilted tube quickly through the 
gas flame. The plug, which has meantime been carefully held, 
is partially replaced and the tube returned to its stand. Treat 
the tube containing the culture (which has been furnished) in — 
the same manner. Then place the two tubes side by side 
between the thumb and forefinger of the left hand, palm facing 
upward, and grasp them about the middle of the upper half 
(see Fig. 38, p. 108, Crookshank). Sterilize the platinum 
loop by passing it through the gas flame, care being taken that 
the handle is also flamed for a distance of at least 15 cm. 
Then carefully remove the plugs from the tubes and hold them 
between the fingers in such a manner that the tube ends, pro- 
jecting outward, will not touch anything during the inoculation 
process. Insert the wire loop carefully into the culture and 
transfer a loopful of the culture to the tube of bouillon and 
gently rinse it from the loop. The loop is then withdrawn, the 
