HISTORY OF BACTERIOLOGY 
iii 
A drop of water from the neglected vase of flowers 
will often give similar interesting phenomena. 
The modern work upon bacteria was begun and the 
foundations of the science of Bacteriology were laid 
when Louis Pasteur in France, less than sixty years 
ago, began to grow and cultivate these dust-plants. 
Since then the advance in knowledge about them has 
gone on with ever increasing rapidity. 
If it is possible to increase the power of the micro¬ 
scope or to so train the human eye that it may see 
more than is seen at present, would greater wonders 
be revealed? Such a possibility is ever before the en¬ 
thusiastic student. 
About twenty years after Pasteur, Robert Koch de¬ 
clared that he believed bacteria were the cause of dis¬ 
ease and not the effect, as many had thought them to 
be. He began to grow bacteria on potatoes and in 
other ways then new, but now common. These are 
known as “solid cultures. ,, 
This was a great advance toward the discovery of 
disease germs, because by the differences in their be¬ 
havior or growth on different substances it was pos¬ 
sible to separate the species. 
The farmer knows that the same soil is not equally 
good for corn and melons and that a pine tree will 
flourish where a willow would die. These are at the 
other extreme in the plant world from the invisible 
bacteria, but the microscopic forms have their prefer¬ 
ences in food and their favorable and unfavorable 
conditions, as well as their well-known giant brothers. 
Work of 
Pasteur 
Koch’s 
Theory 
