Luis Pasteur, a professor of chemistry at the university of Lillie in Northern France, watched that sour wines contained barely visible rods and sticks, that could make people sick. In 1857 Pasteur wrote a note relating microbes to illness and set the foundation for the "Germ Theory of disease", against the theory of "Spontaneous Generation of Life" (meaning life originates from nothing and all by itself in the presence of air and food). The theme of the germ theory claims that there are some life forms that may grow/multiply in the presence of food and air, and these two elements are no way connected to the creation/origin of life what so ever.

To make the broth germ free, two sets of container with the broth were heated up

Day 0

Day 1

Day 0

 Day 1

Criticism: Life ("Life-Force") in the air was  destroyed by heat.

• In this experiment the broth was sterilized, and the neck of the bottle was extended like a tube, as shown in the above picture.
• The end of the tube was sealed, the broth remained sterile.
• The tip was nipped, that allowed air to enter the container, but the dust were trapped, and the broth remained sterile.
  • Under this condition if the container was tripped, allowing the broth to touch the dust trapped along the container wall, the life forms started growing in the broth.