Pasteur believes that the concentration of microorganisms in the air is related to environmental conditions, air movement and altitude  He opened bottles of boiled medium at different heights on the mountain and found that the higher the altitude, the less likely it was to be contaminated by microbes  At the top of the mountain, only one of the 20 bottles filled with culture medium grew microbes
As long as there is oxygen stimulation, microorganisms will grow spontaneously from the culture medium
 Puchet repeated Pasteur's experiment with hay extract, but came to a different result: even at high altitudes, all the bottles containing the culture medium quickly grew microbes