6 Pasteur on Spontaneous Generation. 
organisms in the several flasks are different. This result might 
have been expected, for by limiting the rush of air and repeating 
it with different flasks, a small number of germs would be col- 
lected in a limited portion of air and the growth of these germs 
would not be obstructed by other germs, more numerous or 
more vigorous or rapid in their growth, capable of monopolizing 
the soil to the exclusion of those less vigorous or less rapid in 
owth. 
It was found that the number of. negative results varied | 
greatly with the atmospheric conditions, and that nothing was 
easier than to increase or diminish the relative proportion of 
flasks which gave birth to the organisms mentioned, or the num- 
closed in the cellars without the disturbance of the air caused by 
the entrance of the operator there would be the same absence of 
vitality in the flasks filled with air from that locality as if they 
were filled with air exposed to a red heat. 
he following results were obtained by Pasteur with flasks 
opened in widely different localities : 
