CHA Pek Vii 

THE PRESENCE OF GERMS IN AIR AND WATER 
it would be useless here to dwell at any length 
upon the mere speculations of Spallanzani con- 
cerning the universal distribution of germs in the 
atmosphere, and the subsequent experiments made 
by Pasteur up to the date of the publication in 1862 
of his “ Mémoire sur les Corpuscles organisés qui 
existent dans l’Atmosphere,” in which he attempted 
to establish a foundation of facts in conformity with 
these speculations. At first Pasteur was inclined to 
believe with Spallanzani that germs existed every- 
where in the atmosphere; that they were, in fact, 
universally diffused—though he afterwards _pro- 
mulgated a very modified form of this doctrine. 
He was compelled to surmise that they probably 
exist in veins or areas, variously interblended with 
germless regions of the atmosphere. 
In addition to what were supposed to be 
“organised corpuscles,” other fragments and foreign 
particles of the most varied nature were met with— 
though the kinds, relative proportions, and actual 
abundance of the different solid bodies varied 
extremely with the nature of the locality in which 
the air was examined, and also with the state and 
tranquillity of the atmosphere at the time. 
39 
