Larazzo Spallanzani
Spallanzani was an Italian priest born in 1729. In his early life, his father was a lawyer, and he wanted his son to do the same. However, Spallanzani showed no interest in law, and would rather do things related to animals and science. Later in life he became a priest, while also studying science.
In1745, John Needham, an English clergyman, thought that he had found the definite way to prove Spontaneous Generation. A commonly known fact was that boiling liquids would kill any microorganisms. So, Needham wanted to test and see if microorganisms would still appear after boiling a liquid. He boiled chicken broth, put it into a flask, sealed it, and waited. Soon enough, microorganisms grew. Because of this, people started to believe in Spontaneous Generation even more.
However, when Spallanzani heard of this experiment, he did not believe it. Spallanzani proposed that the microorganisms could have entered the flask after it was boiled, and before it was sealed.
In order to test Needham's theory, Spallanzani put broth in a flask, sealed the flask so that way no air could get in, and boiled it. No organisms grew in that flask. Many people said that all that Spallanzani did was prove that Spontaneous Generation did not occur when there was no air.
In1745, John Needham, an English clergyman, thought that he had found the definite way to prove Spontaneous Generation. A commonly known fact was that boiling liquids would kill any microorganisms. So, Needham wanted to test and see if microorganisms would still appear after boiling a liquid. He boiled chicken broth, put it into a flask, sealed it, and waited. Soon enough, microorganisms grew. Because of this, people started to believe in Spontaneous Generation even more.
However, when Spallanzani heard of this experiment, he did not believe it. Spallanzani proposed that the microorganisms could have entered the flask after it was boiled, and before it was sealed.
In order to test Needham's theory, Spallanzani put broth in a flask, sealed the flask so that way no air could get in, and boiled it. No organisms grew in that flask. Many people said that all that Spallanzani did was prove that Spontaneous Generation did not occur when there was no air.
The image on the top shows how John Needham conducted his experiment. Because the flask was not sealed, microorganisms were still able to get in after the water cooled down. The bottom image displays Larazzo Spallanzani's experiment. Due to the fact that the flask was sealed with a cork before it was boiled, no microorganisms were able to enter.