THE DARK DAYS OF THE WAR 149 



keep them from the intruding organisms that caused 

 them to deteriorate. He could usually predict by 

 a microscopic examination the particular defect 

 from which a beer was suffering. Pasteur inves- 

 tigated not only the diseases of beer, but many 

 phases of the process of brewing. He did not like 

 beer, but he had friends enough who were not un- 

 willing to pronounce upon his various samples. 

 "Give me a good bock," said his friend Bertin, 

 "and you can discourse learnedly afterward." 



The results of his elaborate researches are 

 brought together in a volume entitled, Studies on 

 Beer, which was dedicated to his father. The 

 practice of heating bottled beer to kill its many 

 ferments dates from these investigations. The 

 French speak of "pasteurizing" beer and wine as 

 we speak of pasteurizing milk. French beers be- 

 came practically as good as the beers produced in 

 Germany and the Congress of French Brewers 

 meeting in 1889 gave to Pasteur the credit for the 

 great improvements which had been made in the 

 brewing industry. Nowadays brewers are as care- 

 ful of their strains of yeasts as an agriculturist is 

 of his breeds of cattle and sheep. 



