58 BACTERIOLOGICAL DIAGNOSIS. 
from the air, and the glucose is added to absorb any 
oxygen which may be in the medium. To increase our 
chances of obtaining this bacillus in pure culture the 
material to be examined is to be heated to a tempera- 
ture which will kill all developed bacteria, but which 
will not be injurious to spores; the tetanus bacillus is 
the only anaérobic organism with a spherical terminal 
spore which is at all likely to occur in a wound. 
Method.—The inoculations are to be made with a 
pipette. If the pus which comes from the wound can 
be drawn up into the capillary tube of a glass pipette 
such as is described on page 41, the material should be 
collected in this way. If this is not the case the wound 
must be scraped with a sterilised platinum needle or 
other suitable instrument and the material thus obtained 
mixed with some boiled water (previously cooled) and 
then sucked up into the pipette; the end of the latter is 
then to be sealed in the flame, care being taken that the 
material itself is not heated. 
Having filled and sealed the pipette, heat some water 
in a small flask or large test-tube until it reaches 80° C., 
as measured by the thermometer; insert the sealed end 
of the pipette in the water and maintain the tempera- 
ture for ten minutes. The thermometer is to be kept in 
the water the whole of the time, and the flame is to be 
taken away when the temperature rises above 80° C. 
and reapplied when it falls below that point. 
At the end of this time the pipette will contain no 
living object other than spores. Break off its point and 
insert it gently into the glucose agar, taking care to 
keep exactly in the axis of the tube, until the tip of the 
pipette reaches almost to the bottom of the test-tube. 
Withdraw the pipette gradually, blowing out its con- 
tents as you do so. The spores of the tetanus bacillus 
