Lazzaro Spallanzani's Experiment

Lazzaro Spallanzani - One of the first to disprove spontaneous generation. An Italian scientist who proved microorganisms could be killed by boiling. (Italian 1767)

Spontaneous Generation


Spallanzani's Problem

What causes microbes to form in decaying broth? 

Hypothesis: Microbes come from the air. Boiling will kill microorganisms.

Spallanzani put broth into four flasks

Flask 1 was left open 

Flask 2 was sealed

Flask 3 was boiled and then left open

Flask 4 was boiled and then sealed

Spallanzani's Experiment Step 1

Flask-1

Left Open 

Turned cloudy

Microbes were found

Spallanzani's Experiment Step 2

Flask-2

Sealed 

Turned cloudy

Microbes were found

Spallanzani's Experiment Step 3

Flask-3

Boiled and left open 

Turned cloudy

Microbes were found

Spallanzani's Experiment Step 4

Flask-4

Boiled and sealed 

Did not turn cloudy

Microbes not found

Spallanzani's Experiment Results

What did Spallanzani's experiment show? 

Was his hypothesis correct or incorrect?


Return to Spontaneous Generation Page

If you would like to comment or ask questions, contact: Webmaster

Copyright ©, 1998 Tim Lynch


Copyright (c) 1995-2001 by the author(s) - All Rights Reserved