PASTEUR ENTERS THE CONTROVERSY 243 



flask. Pasteur concluded that the amount of dust and germs 

 in different localities must vary. In reporting this experiment 

 to the French Academy of Sciences, he stated that the study 

 of the germs which accompanied dust might lead to a knowledge of 

 the origin of various diseases. But the conception of germs and 

 disease was so vague that no attention was paid to this statement. 



While Pasteur was conducting his experiments in the Alps, 

 Pouchet was testing air in Sicily, on Mt. Etna, and on the sea. He 

 found microorganisms in all his air tests. Many people believed 

 in the validity of Pouchet's work rather than that of Pasteur's. 

 One scientific journalist wrote that Pasteur's work was too fantastic 

 to be exact. 



Then Pouchet decided to repeat Pasteur's experiment. Accom- 

 panied by two other scientists, he departed for the Alps with a 

 number of narrow-necked flasks filled with hay infusion. At the 

 foot of a glacier of the Maladetta, 3000 meters above the sea level, 

 he opened four of his flasks. Then the tubes were carefully sealed. 

 Microorganisms soon appeared in the flasks. Pouchet then con- 

 cluded, since there was no dust at the place where he had opened 

 the flasks, that air did not bring in the germs, but that they 

 must arise by themselves from the organic material. 



The debate became so heated that the Academy of Sciences 

 appointed a commission to examine the experiments of Pasteur 

 and Pouchet. Both scientists were invited to present their experi- 

 ments, but Pouchet said the weather was so cold that it might 

 compromise his results. Some time later, Pasteur was invited to 

 give a lecture on spontaneous generation at a scientific meeting at 

 the Sorbonne. A theatrical performance could not have drawn a 

 larger crowd. Every seat in the room was taken and many 

 scientists and students were there. Pasteur simply and care- 

 fully performed his experiments, explained them, and presented 

 his conclusions. He explained to the audience that boiling 

 destroyed the germs, but if air entered after the boiling, it carried 



