Chapter VI 
MAN’S FIGHT AGAINST MICROBES 
N OT until about two hundred years ago 
did anyone imagine that there were such 
things as microbes, and it was a hundred years 
more before anyone knew that they had any¬ 
thing to do with disease. Up to that time there 
were all kinds of queer ideas as to what made 
a man sick. 
One of the earliest beliefs, and one that many 
savage tribes still have today, was that illness 
was caused by an evil spirit, or demon, which 
had entered the body of a man and caused 
trouble there. The only method of cure for a 
sick man was in some way to get the evil spirit 
to leave him. The medicine man, who was the 
primitive doctor, might try to persuade the 
spirit to come out, by prayers and promises; or 
an effort might be made to force it out, by the 
How long have 
we hjiown 
about microbes? 
85 
