BACTERIOLOGY IN A NUTSHELL. 
An Assistant’s 
Mistake. 
II. —The number of bacteria to be destroyed. 
If a large number are present more of the solu¬ 
tion is necessary than for a small number. Com¬ 
pletely saturate the mass always, for whatever 
number. 
III. —The temperature and strength of the 
solution. Hot disinfectants are more effective 
than warm or cold disinfectants. 
IV. —Material with which a solution may come 
in contact. If some disinfectants come in contact 
with organic matter, they are rendered of little or 
no value thereby. The writer remembers seeing a 
pupil nurse sent three times to empty out and 
prepare anew a disinfectant solution because an 
assistant put his soiled finger into the first two, in 
order to test the temperature, and was about to 
make the same blunder a third time when pre¬ 
vented by the whispered admonition of the head 
nurse. The lesson is plain. 
Hot air, steam or boiling water, are all disin¬ 
fectants or germicides. The value of hot air or 
dry heat as a disinfectant is limited, as there are 
so many things which cannot be disinfected by 
either without being injured. Moist heat is more 
penetrating than hot air, and mattresses, clothing, 
and surgical instruments can all be treated by 
moist heat without sustaining injury. Clothing 
stained with pus, or fecal matter, should not be 
disinfected with steam heat, as the stains will be 
found difficult, if not impossible, to remove after¬ 
ward. 
Boiling water is warranted to destroy all 
known bacteria or their spores if exposed to its. 
power for a sufficient period. 
74 
