NINETEENTH-CENTURY MEDICINE 



phere free from germs, will dry up gradually, without 

 the slightest sign of putrefaction, regardless of the tem- 

 perature or other conditions to which it may have been 

 subjected. Let us witness one or two series of these 

 experiments as presented by Pasteur himself in one 

 of his numerous papers before the Academy of Sciences. 



EXPERIMENTS WITH GRAPE SUGAR 



" In the course of the discussion which took place 

 before the Academy upon the subject of the generation 

 of ferments properly so-called, there was a good deal 

 said about that of wine, the oldest fermentation known. 

 On this account I decided to disprove the theory of M. 

 Fremy by a decisive experiment bearing solely upon 

 the juice of grapes. 



" I prepared forty flasks of a capacity of from two 

 hundred and fifty to three hundred cubic centimetres 

 and filled them half full with filtered grape-must, per- 

 fectly clear, and which, as is the case of all acidulated 

 liquids that have been boiled for a few seconds, re- 

 mains uncontaminated although the curved neck of 

 the flask containing them remain constantly open dur- 

 ing several months or years. 



" In a small quantity of water I washed a part of a 

 bunch of grapes, the grapes and the stalks together, 

 and the stalks separately. This washing was easily 

 done by means of a small badger's- hair brush. The 

 washing-water collected the dust upon the surface of 

 the grapes and the stalks, and it was easily shown under 

 the microscope that this water held in suspension a 

 multitude of minute organisms closely resembling 

 either fungoid spores, or those of alcoholic yeast, or 



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