BACTERIOLOGICAL TECHNIQUE. 935 
perforated by glass tubes drawn to a point are filled to 
such a height that when the fluid is heated to 80° C. 
it will just fill them. They are inoculated when the 
bouillon is at about 60° C., heated to 80° C., and then 
sealed by closing the tube’s point by means of a flame. 
After inoculating and heating, instead of sealing the 
glass tube a sterile rubber cork can be inserted. If 
much fermentation is expected, the cork should be 
clamped or tied to the bottle, so that it will not blow 
out. One advantage of this method is that any con- 
taminating organisms which have no spores will be 
killed. When sealed the bottles should be cooled and 
then placed in the incubator. 
