THE MICROBE 
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same temperature. Some microbes are able to 
multiply at, or very near, the freezing point, 
while others are known to multiply at a heat of 
138 degrees. One microbe is known that lives 
continuously, and multiplies, in the water of hot 
springs at a temperature of 159 degrees. 
Microbes which live in animals or men have 
a much smaller range of temperature than those 
which live in the outside world. The favorite 
temperature for microbes that are harmful to 
man is near the average temperature of the 
human body, which is about 98 degrees. Most 
microbes are killed in temperatures of 131 to 
136 degrees, if kept up for ten minutes in moist 
surroundings. 
Microbes can stand low temperatures better 
than high ones. The common microbes of 
water and soil, and also those of typhoid fever 
and diphtheria, have been left for several days 
at a temperature of 310 degrees below zero with¬ 
out destroying their life or their ability to mul¬ 
tiply again when the temperature was raised. 
However, if these microbes are in water which 
